Great video, problem solved for me, thanks. I live in Portugal and we have TT systems here and here they sel this inverters for off grid use only. With this setup we will be able to use it on grid too. Thanks again.
Very interesting subject, very informative thankyou for your time ! I recently upgraded from and standard inverter to a hybrid and came across this issue, I am currently using it Off-grid but I will hook up relay via dry contact when winter comes !! Thanks again 👍
Thank you for making the video. The inverter manufacturers/sellers did not provide much details about the Lines, Neutral, Ground. I even ran into a comment about where to connect L1 and L2 on a device that has L1 and Neutralports only. The manufacturer replied use L1 as the first hot and Neutral as the other hot line. Well, at least there is an answer...but then what do we do with the Neutral and Ground line; I am asking because there must be a good reason why they bother using Neutral and Ground wire. This is very frustrating trying to get information! I feel like not many actually address the wiring of L1, L2, Neutral, Ground! Some people even be making about you don't need Neutral if you are using 240v. 🤦♂️
hi. there is a simple answer. do not use inverters built for other regions, especially when there is a totally different electrical system then in yours. if you live in US system, use US L1 L2 devices. using LN devices will prohibit you from earthing that device properly when in grid connection.
the victron mutliplus internal relay also open and close the ground bound depending if it's in it's transfer mode or standalone inverter mode but i'm still didn't make up my mind about how to install it in beginning, i was thinking about bounding neutral to ground rod, but realized maybe i should just earth the inverter chasis, and the internal relay will do the rest the inverter also have an independent auxiliary ground relay socket to control an external contactor
Hi Roland, I believe I have exactly the same booklet where it discusses the relay contact positions of the "Dry Contact" terminal block. I paused your video at "15:47" and compared the wording from your book to mine. It appears to be identical with the exception that the program numbers used in my book are different to yours, ie #20 and #21 for you, but I have #12 and #13. However, I believe that is semantics only, but are referencing the same settings. There's one bit I'm not sure I follow 100% correct, and I was hoping you may have noticed this yourself, or could help me understand this better. The table states that for the following conditions..... Unit Status = "Power On" Condition = "O/P is powered from Utility" "NC & C" - Close. "NO & C" - Open Which means that the "NO & C" contacts would be "Open". And....as you have illustrated in your video, this would remove power from the Earth Bonding relay, and consequently remove the Neutral-Earth Bond and restore the TT Earthing Technique as per Grid Supply, AKA No local Bonding 🙂 Sounds Good and appears logically correct to me. You then go on to say at "17:04" in your video .... "So when the machine switches over to the Off-Grid Mode the Normally Closed (NC-C) will then be open, and the Normally Open (NO-C) will be closed. And this is what we need to know....." By definition and logic this action would then bond the Neutral and Earth for Off-grid operation, however.... now that the "Condition" of the device has changed to "O/P is powered from Battery or Solar" and we review the table, there also appears to be other conditions we need to verify to see what state the "Dry Contacts" will move into when it goes back to the "Off-Grid" mode. Let's assume we have set Program #1 to "SBU" or "SOL". If it's a bright sunny day, and your batteries have reached full charge set by Program #21 (My Program #13), then according to the Table the "NO & C" will Open. My assumption is that the Device will still remain in Off-Grid Mode, but the Neutral Bonding to the Earth will then drop because the Relay is de-activated. In another example which I believe would have unfavourable outcomes would be if you have Program #1 set to "UTL", and for whatever reason the Battery Voltage fulls below the threshold of the "Low DC Warning voltage". Which I can only assume would push power through from the Utility Grid Supplier. This condition appears to close the "NO & C" contact, which would re-enage the Neutral Bonding to the Earth, even though we are using Grid Power. Not sure if I'm mis-interpreting how the "Dry Contact" NC - C - NO relay contacts work, but your advice, knowledge would be appreciated.
Hi Jeff. You are right! I have looked into the booklet and came to the conclusion that the writer or translator of that booklet didn't have his brightest day. This table is used by every single device manufacturer but cannot be right. If the main column is separating between Output on utility or output on Battery, that it shouldn't be possible that when conditions of battery modes which require the contact to switch to utility are doing exactly the opposite of what the main statement is telling. I will research this on my device and release a video on how to do it correctly. Just follow the instructions on the table regarding the battery mode (I am sure you want to use the inverter in Solar mode). This seems to be correct. But because the contact position will be different now, we need to use the dry contact of the Transfer switch in a daisy chain to open the bonding relay when the inverter is shut down. I will explain that in the new video...Thx
@@RolandW_DIYEnergyandMore I'm glad you came to the same conclusion I had, ie "Utter Confusion" with the table :-) ...I checked, double checked, and triple checked my theory...AND...without having my Inverter installed and powered up yet, I am unable to test it myself. I'm waiting for my EVE LFP Cells to arrive so I can construct my 48V 13Kw Battery, and in addition, I need the time to install my Solar Panels on the roof, so I'm all theory at the moment. I'd be interested to see what you come up with in comparison to what i discover with my Hybrid Inverter, when I build my system. Thanks Again. Not 100% sure what your plan is with your "Change Over" switch, but it seems like it has a separate set of contacts (low current) that you are planning to put in series with your Off-Grid Device "Dry Contacts" to create a Boolean "AND" operation to control the Neutral-Earth Bonding.
@@jeffclarke7990 yes. The table seems to be correct. I checked it on my inverter today. Just don't really know when the basic option of "Output is powered from utility" can actually be met as you can run the inverter only from one of the 4 modes in item #01. The dry contact then is primarily controlled by the two set voltages (Batt low and Utility return) which will command the switch to the grid when in SOL, SBU or SUB mode. As I said. I do assume you will run the device on SOL anyways, so the dry contact to be used is NC. This gives us the conflict of being in the same state as when the inverter is shut down. But for this case we can use the highly recommended ATS, which typically has a dry contact as well, to use its contact in series as you have noticed. The ATS dry contact will open when it is "changed over" either automatic (if the inverter fails) or manual (when doing maintenance, etc) and release the N-G bond.
Hi Roland! Great video. In my US system, I am grid tied on emergency backup, my grid input panel is neutral-earth ground bonded. My 6 split phase inverters terminate on my load output panel that is not bonded, but goes to my input panel. My inverters switch the NEG bond when in DC mode. Many have recommended that I need to remove the inververter internal NEG bond. One person said I need only one inverter relay, per Viktron instructions. Appreciate your insight! -Jay
Hi. As you do have so many inverters i would say that one, but that to be an external high power bond would be preferable. Imagine if fault current powered by 6 inverters go trough an internal NEG bonding relay of a single inverter which was designed for its own power level. I wouldn't remove all bonds as then you would render all your GFCIs useless as well as MCBs which might do its job as you seem to have that extra power from the 6 inverters ;) In general inverters have their built in short circuit protections and will eventually shut down...
@@RolandW_DIYEnergyandMore thanks Roland! So to rephrase, with my supply side neutral-ground bond (NB), I can safely remove all inverter’s internal NB?
@@jcschwarb your supply side bond is not passed through the inverters when in off-grid mode (i think that is what you have called DC mode), or is it? It is right that the inverters switch a NEG bond when disconnected from the grid input, but of course if all 6 are doing that, then you get 6 different fault paths. It would be better if a single external relay is doing that job. Its hard for me as i do not know your actual setup and don't know if your inverters have a dry contact.
@@RolandW_DIYEnergyandMore Thanks again Roland. Not sure how to resolve this. Hoping the manufacturer can provide direction as I think this is their issue to fix since they are selling the solution that I am trying to configure per their manual that doesn't cover any of this topic. I am having a hard time getting both phases to run together, only phase B is working currently when I energize up to four at a time.
During testing yesterday, my no. 3 inverter had a catastrophic failure with a loud pop that caused all other inverters to shutdown immediately. Trying to understand what caused this. I only had 6 48v batteries applied. Was this possibly due to the NG bond issue?
Thanks Roland, please do more video about this topic (TT earthing system with off-grid solar inverter) Many inverters in my place don't have dry contacts or any similar provisions! What shall we do to make our installation SAFE?
@UA-cam user, which type of inverter do you think of when you say Off-Grid without Dry contact. So, you still have an Off-Grid inverter with AC-In which you are trying to use when the Battery is flat, right? Or are you purely Off-Grid? Then you don't need to care about the Grid System around you at all. Just build your own TN-S setup as shown in one of my other videos. As XXX is noting, the only other way is to use an Automatic Transfer Switch, which will switch over to the Secondary Source once the Inverter stops. But that switch is not seamless same in the All-in-One inverters who can switch over similar to a UPS. So, there will be a gap of 1-3 seconds depending on the model of ATS. The TT-Earthing system makes a solution quite inflexible. You have to consider the equipment which you can use there
Well explained and much appreciated, its not obvious when you buy these all in one inverter you need a ground neutral bond in battery mode, though wonder can the mentioned load center then go through a transfer switch to consumer unit on power outage ?
A transfer switch will always be à good way to create isolated circuits behind 2 different power sources. Its just important to put the N-G bond on the right place if one source must be bonded and the other doesn't.
@RolandW_DIYEnergy ok so we do not need to use the contact relay, just bound the off grid source before going into the transfer switch ? guess ?? TIA, p.s. for clarification we have similar china all in one inverter like your, and only use one socket for small loads (permanently) and only transfer on power cuts.. it is only using solar to charge grid not connected...
OMG! Thanks Roland. After my last comment, I figured out that TT system is actually used in my country and I have been researching how to do this with Growatt SPF 5000 ES based on your other video. It is now crystal clear to me how I can do this on inverter's AC output side. But I do have a question for AC Input's side ground. Please let me know if I should bond the AC Input ground to load center's Ground as well.
Well, in a TT system you wouldn't have an explicit AC in Ground :) Did you ever measure, if Ground terminals for In and Out arn't actually one anyways?
@@RolandW_DIYEnergyandMore Thanks, Roland. It took me a month to figure out this complex topic. This is my latest finding so far. My inverter seems to be from a newer batch, so it does the N-G bonding internally on battery mode and breaks the bonding on grid mode. So that means I don't have to use the method mentioned in this video. I understand that the inverter on battery mode turns the system into TN-S since the AC input is disconnected and isolated internally. I measured 0.001v between N and G. In grid mode, the system becomes TT since AC input and output are connected, and I need only to connect the AC output's ground to the earth. But I found the voltage between N and G is now 10v. Is this expected "Stray Voltage", or can you enlighten what I am missing here?
@@tibuuso I'm no expert at this, nor do I have the experience that Roland has, but in a TT system I would expect that the voltage maybe straying, because the Earth to Neutral bonding is done at the Transformer, and there is a large impedance between the Supply side's Earth Rod at the Transformer Source and your local Earth Rod in the ground. I'm happy to stand corrected on this matter, but the whole subject of Earthing Families and their subsets is a fascinating subject to say the least.
What happens if the relay has a fault, i.e.: broken coil? Or the opposite, what if the relay is blocked and does not release the contact? I mean, the grounding system is thought to be there to protect in the case of faults, adding a relay just adds up another thing that may fail.
Hi. Yes, every extra device in a circuit is another point of failure. Relays are luckily very simple and rarely failing items especially when you consider that under normal circumstances there is no current flowing over it. If it fails to close the bond, then your system will turn into an isolated system. There is nothing bad in that scenario as long as there is no secondary isolation failure within your grounding system. You will just run the inverter as probably most other people do. Multiple grounding failures might even turn an installed RCD (which in an IT setup is useless) sensitive again as the installation is turned from IT to TN. The DIN rail relays typically have a small indicator on them which shows the state of the contact. So, you can see if it fails to close if it should have. If it fails to open because the contacts are stuck together, there will be an unwanted N-G bond while you are connected to the TT-Grid. If there are leakages somewhere on your transformer client's group, you will see a current flowing over your bond. These currents will typically not be high as they are just picked up by your grounding rod, as well they won't be dangerous but they will be there and cause confusion :) Your own installation will still be safe under this condition as there is a present ground loop available for the RCD to detect faults. Just always check your system. Everything shall be maintained. The inverter could have a similar problem if it has an integrated relay and it fails...
I. Understand why such relay is sensing the difference between Grid power and inverter powered by batteries as by norm common installations (grid power)would already have a neutral to earth bond before the consumer unit itself TN-S system. In such way that there would always be one ongoing bond of this sort at a time preventing possible transient currents and most importantly allowing the Residual current device or RCBO’s to detect unbalance current between live and neutral hence tripping and isolating the supply under leakage to earth fault condition. May i just point out that in a complete off grid electrical installation no such relay would be necessary and one bond would be necessary at the consumer unit itself.
Great video. I am in the UK and my house grid system is TN. I have bought an easun hybrid inverter that has the option for the internal earth neutral bonding. So my solar system will be offgrid with the option of using "line mode" in the inverter during the winter to charge my batteries using cheap night time electricity. If I use the inverter internal option of earth to neutral bonding do I still need the relay using the dry contact or is it better to use the dry contact with the relay on my off grid consumer unit instead of the inverter earth to neutral bonding? I assume if I use the inverter earth to neutral bonding then it will be connected to my house TN earthing system via the mains line mode connection. Keep up the amazing work 👏
Hi. Is it possible to program the internal link via the inverters UI by mode or would that bond be permanent? If it is settable, then you wouldn't need an external relay. Nevertheless, the external option is the better one as you can use high current relays for bonding. The internal relay might not be powerful...
Great Video! What is the situation in peak shaving mode? That case some power coming from the solar and some in same time from the grid? This system can use 3 input mode at same time.. - grid - battery - solar Really crazy to handle earth protection by proper way.. or just must believe the Chinese engineers..😀
well...such inverters are primarily grid tied inverters which store excess energ in a battery and give it back when required. Being completely off-grid and requiring the seperate N-G bond will only happen when the grid is down, right? So you would need the bonding relay for that "Emergency Power" case only. Maybe the inverter will have a bonding relat built in already. Yes, earthing get get very complex and that was exactly why I started this videos to get discussions going and increase awareness when people DIY. Thx
Going deeper down the rabbit hole, my gosh :) As i said in one of your previos video i have Deye Sun 6-K single phase all in one inverter. As we comment already about my neighbourhood trsnsformer grounding system TN-S (but it appear my house have TN-C because my home DB dont have PE bus bar) and i will use additional grounding rod connected on main PE copper wire which goes in main supply DB where also my house DB connect, i hope this does not apply to me!? I checked manual. There is no such table here, nor i have info if my inverter have internal ng bond. As per manual they state only this: This diagram is an example for application that Neutral connects together with Protective Earth in distribution box. Diagram say that Grid-connection port PE line connects to neutral in house DB, but backup-connection port (off-grid ups port) PE leave disconnected while backup-connection port Neutral connects to Neutral of grid-connection port which is already connected to PE line. Am i safe to forget this story about dry contacts reley connections? I mean there is no such theme in manual as you are discussing here! God bless you mate.
What I have read till know, I think you have misinterpreted what earthing system you have. The earthing system of your house is defined by what you have delivered into your DB. If you get 2 wires in from your utility and somewhere right after there is a split of Neutral where your PE is born at that point and connects to the PE bar, then you have a TN-C-S as probably most other people will have. If there is no split of utility Neutral into two, and your PE wire which connects to the PE bar is coming straight from the rod at your parking, then you have a TT system. But in any case. The Deye SUN6K is a grid interactive Hybrid inverter. It is basically a grid-tied inverter with off-grid backup. So, you need to connect it as any other appliance in your house using L, N, PE as there is. The question is only what the N-PE status will be when the grid is down and if it will provide a N-G bond in that case or if your installation will then run isolated. It doesn't really matter in that case. But maybe there is an internal bonding relay which can be set in the UI for the case when the inverter is off-grid. You are good to go to just connect your inverter to the existing PE bar of your house.
@@RolandW_DIYEnergyandMore Thank you Sir. Roland for explanation. English is not my language (i am from Croatia :)) so sometime i get lost in writing sorry ;( I will try to explain better now. Some twenty or more years ago we had electric coming from aerial poles to my house. In that time we had TN-C system of grounding and all house wires for apliances was two wires only where PE connect to neutral. Then Elektra decided to improve infrastructure, install neighborhod distribution boxes, lay down new underground cables and switched to TN-S ground system. After that, we all was connected to new system but our houses was left on two wires only and our neutral wire was connected to PE wire in these big neighbour distribution boxes. Thats why i said our grounding system is TN-S but my house appear as it is connected to TN-C system (as before improvement) becouse there is no PE bus bar in my house DB. Meanwhile new houses was built in my neighborhood with three wire laydown system ( L,N and PE) and connected to these new neighborhood distribution boxes, hence that PE copper wire on my brother parking lot and this PE copper wire is connected on PE terminal in big distri box where my house is also connected. So this is same wire my house is using but on different way. I hope my explanation have more sense to you now :(
@@RolandW_DIYEnergyandMore Or maybe we realy have TN-C-S system. I will check later with my electrician. Its half past seven and its Sunday so i will bother him later with coffe and nagging :))
@@RolandW_DIYEnergyandMore Thank you for easing my mind Sir. Roland W. And thank you for your comment about my inverter. I hear more and more good words about Deye products. I needed that coz when i bought it i didnt know a squat about it :) Cheers mate
Thank you for the video. I have a question? Is it mandatory that a grid tie inverter to have a neutral AC connection? We have a 127/220V 60 Hz TT grid case 1: Grid tie (not a hybrid) split phase inverter. Is a inverter neutral AC connection mandatory and must it be connected to the grid case 2: Grid tie (not a hybrid) 3 phase inverter. Is a inverter neutral AC connection mandatory and must it be connected to the grid Thank you Andy
Without a neutral you cannot create an earth fault loop. Technically for certain types of loads a phase to phase (split phase or 3-phase) is perfectly suitable, but an inverter tied to the grid will still need to be connected the way it is designed. And that will require a Neutral and a Ground connection as well. So, by probably any national code it will be mandatory.
Hallo Erik. Bei Themen welche Ich denke gut in Deutsch ankommen sollten, versuche Ich es ohnehin. Nur sind bis dato meine deutschsprachigen Beiträge kaum angesehen worden. Und bei den meisten Themen müsste Ich die ganze Zeit darauf hinweisen das in der folgenden "Dauerwerbesendung" es um Dinge geht welche "niemand nachmachen sollte oder darf" :) Der deutschsprachige Raum hat viele talentierte UA-camr die es auch verstehen ein wenig Geld aus ihrer Aufgabe rauszuholen, dass mir eigentlich nur der etwas unterbediente Teil der (3.) Welt überblieb, damit auch die Menschen hier wenigstens einmal etwas von Sicherheit ihrer elektrischen Installation hören, oder eine Idee darüber bekommen wie sie die persönliche Versorgungssicherheit in Ihrem bemitleidenswerten Stromnetz steigern können :) Also wie gesagt. Es kann durchaus sein, dass es hin und wieder auch Videos in deutscher Sprache geben wird. Generell ist es allerdings viel Aufwand zweisprachig zu filmen und zu schneiden...Grüße nach Deutschland, Oesterreich und Schweiz!
The local utility in the Philippines uses TT system, the inverter is bonded. The problem is after a typhoon the utility post very close to the house is supported now by a cable which has caused a connection between the post ground wire and neutral and its very unlikely it will be fixed, so my question is should my bonded inverter be grounded or should I unbond the inverter and ground it
Nice details Roland. I bought a Solax X1-Hybrid G4 and were I live TT system is used. Excluding the DC part (PV and Battery), the inverter has L-N-PE on AC in, i tested for continuity between N-PE and there is none when the inverter is OFF with nothing connected to it. On AC out there's only L-N, my question is do I still need the relay/contactor to avoid grounding loop when I will be in "grid" mode (using AC from grid because there is no sun and battery is depleted)? From my understanding my answer would be yes but I checked and unfortunatly this inverter seems to have dry contact but It's used only to connect "SolaX Power Adapter Box" that can manage a smart heat pump, i don't think i can command an external relay from that. Thanks in advance
hi. well i guess you will need to achieve a N-PE bond if you want your system work as a grounded system same it is when it is on grid. you would just need to check what you dry contact is doing in each mode of operation. then you can see if it is similarly usable for the external relay.
Hi Roland I am having an issue where my plug and play 5kw inverter trips the earth leakage when power from the grid resumes. Any idea what can be done to prevent this.
Hi. I assume that you have installed the inverter via its AC-In downstream of an RCD. That will usually trip the RCD if the inverter is N-G bonded while on grid power is bypassed through the inverter. So you have to get your bypass grid power from a spot before the RCD or control the N-G bond actively, so that it is only present while your inverter is in off grid mode (bonding relay)
If all inverters are switching between off-grid mode and on-grid mode the same time, only one inverter needs to command the relay. If inverters switch differently, then put dry contacts in series so that the bonding relay will open as soon one inverter goes on grid. Please check you table on modes again about when the dry contact is in which state. We found out its more like mode dependent then simply set by bypass...
Hi, nice video. I will be using a 3K simple pure inverter. Without AC input and only with DC input and AC output without ground. I have an ATS connected before the differential magneto-thermal switch that when it no longer senses the AC output of the inverter it switches to the AC input of the grid. In your opinion in this case what arrangements should I make? If I understand correctly I should put the Neutral to Ground when the inverter is delivering AC and instead disconnect it from Ground when the inverter disconnects AC. I could use dry contacts from the ats since the inverter does not have them! What do you think?
Hi. You actually do not need any special bonding arrangement other than to bond directly at the inverter. The ATS is keeping the bond isolated on the inverter side anyways once it switches to grid. Just be aware to use an ATS which is disconnecting all active lines (phase and neutral)
@@RolandW_DIYEnergyandMore Yes. I have an ats that disconnects both line and neutral. So it's enough that I connect the neutral coming into the ats from inverter with the ground so that when I have power from inverter the safeties work properly
Hi Previously, I have asked you about this issue and you advised a transfer switch. Does this solution remove the need for a transfer switch? Also why would you need the 2 pole relay instead of a single pole relay, for the N G bond? Great content as usual ! Was this a eureka moment for you? I only considered using the dry contact to start a generator, as the manual suggests, lol!
Hi. A transfer switch is still advisable if you need to bypass the whole inverter setup in case of a malfunction or maintenance, that is why the relays should be set up to open when the inverter is off. I was mentioning this already in the practical guidance video but was thinking more of inverters which do have a dedicated bonding relay built into the unit. Then I just noticed, that those units which we are using all come with a dry contact which can be used for the purpose as well. I am showing a 2-pole contactor, because those Din rail relays are available in 2 or 4 pole versions. But if you have a 1-pol, high current contactor, you can use that one of course. But with a 2-pole contactor, you could also bond and start a generator at the same time if you would want to do something like that :). Thanks for watching.
Hi, there is a link to a AliExpress shop in the description for reference. The coil of the contactor is switched by mains voltage through the dry contact. That's how you can switch a 63A relay with a 3A contact. You just need to choose the relay type with AC 220V coil.
One more thing pls , how to wire the dry contact no/c to the relay 1-2-a1-a2 ? I think 1 to the pe bus bar and 2 to the rcd in, a1 to the no and a2 to nutral bus bar. Is that correct ? Advice me pls And tx in advance.
Hi, I have connected a stand alone system with a MUST PV1800 inverter. The system came complete with inverter and circuit breakers in the panel for the solar, battery and 230 volt output. The 230 volt powers a tiny house which has and RCD on the switchboard. If I connect neutral to earth the inverter detects a fault and shuts down with an fault code 03. According to the manual this is "battery voltage too high" but that makes no sense - the battery voltage is no different without an N-E connection. Without the Neutral to Earth bond the RCD doesn't work. Any ideas..?
I have a MUST Hybrid Inverter as well. It doesnt have N-G bond inside... My Earthing system is a TN-C-S one and my inverter is using this very same earth system, but when in off-grid mode, on battery power, there is a voltage measured between N and G on the power outlets, something more then 100 volts for a 220/230V output. Is it normal? Do I have to bond N/G again after the inverter when in off-grid state?
Hi. Yes, you have to make a N-G connection. You can as well use a relay to bond only when in Off-grid mode, but in TN-C-S net, you might as well keep a permanent bond behind the inverter in you load center. Typically it will not interfere with the grid grounding in such a net. I have it that way in my system.
Hi Ronal, I have a problem with the UPS connected to the PC. Let me explain: if I switch to SOL mode everything works. However if I use SBU mode the ups starts to trip as if there is no voltage. I ask everyone if anyone has my problem and has solved it. Greetings from Naples.
Hi. I just compared the SOL to the SBU mode and there is nearly no difference (only some timer-based options). At least not in how the inverter provides power. Why can't you use the SOL mode as your mode of choice if everything is working there?
@@RolandW_DIYEnergyandMore Unfortunately this is the case. I repeat, if I set SOL mode, turn on the printer, hairdryer or coffee machine I don't hear the surges on the ups. If on the other hand, and I can't explain this, I set the ups in SUB mode whether it turns something on or not, it jolts.
Hello again, i was trying to connect the relay the way u told us to do, i have a Growatt 5000 es, i checked for continuity between ground and neutral at the AC out and it was bonded. Before i unbond neutral and ground inside the inverter , i checked for the continuity between the same neutral and ground when the inverter is on grid , there was no continuity between them . So i think for this all in one offgrid inverter there is no need for unbonding neutral and ground from inside the inverter and using this relay, pls check and advice if im wrong, and thanks again for ur helpful topic and ur advice. Waiting for ur reply asap coz i was about to install the relay .
Hi. OK, if that is sure that the internal N-G link is behaving similarly as I am describing the function of the external bonding relay, then the Growatt ES is providing an internal relay already and there is no need for this external modification. Did you also check if the link is open when the inverter is turned off? Later this year, I will demonstrate an extended functionality of an external solution by also daisy-chaining an automatic transfer switch into the control circuit. That might then be another reason to remove the internal link. But as far I see now you are good with that inverter using it in the TT-Grid.
@@RolandW_DIYEnergyandMore Hi,thx for being helpful , actually i did not check before for N-G bonding when the inverter is turned off, but now i checked it, and it was bonded when the inverter is turned off. But thinking is that a problem ? Waiting for ur next demonstration 😍😍 Keep walking GOOD LUCK
@@rabihghannoum1198, probably there is no problem because I think that the inverter when Off will surely not bypass to the Grid and the AC Output will just be powerless.
Great video!!I am going to install growatt 5000 es in Bangladesh, also have TT system. Looking at your diagram you have a separate grounding for inverter. Will it conflict with ac in port which will have currently installed house grounding ?
There is no separate grounding for the inverter. It is connected to the house grounding. The TT-system doesn't provide an utility ground for the AC-In. That is the reason why we need to use the bonding relay to provide grounding link in Off-Grid and disable when On-Grid. Be aware, that the Growatt 5000 is known to come with an internal N-G bond in some countries. If you find your N and G terminal having continuity, then the internal bonding screw needs to be removed for the TT-system. You can watch some US YT channels which are covering that story.
@@RolandW_DIYEnergyandMore I have purchased this inverter from a US authorized supplier (internally modified) and checked the continuity with volt multimeter to confirm there is no bond between N & G. I have also purchased the relay as you instructed. Thank you .
A Grid-interactive hybrid inverter in his normal mode, is equal to a grid-tied inverter. It doesn't matter if you export or use an export limiter. So it will use the grounding system provided by the grid. Only when it switches into off-grid mode when the grid is not available, you would have to provide a N-G bond. Maybe your inverter does have a relay signal to do this, or even has an internal bonding relay? What is your inverter?
I dont agree on using a big relay current (63A?) fo the Ground-N bonding justified by the fault ground current from the neighborough premises. On the contrary the G-N bonding is by definition a Zero current bonding in normal operation WITH battery (Isle system) and fault current must/can be avoided by a normal low Amp FUSE together with a low current relay. The lost of the G-N link must not be a problem with majority of the appliances, only few of them are (without damage) sensitive
Fault currents caused by L-G faults are high current by nature. In an islanding system they will typically be restricted by the surge capability of the inverter. For example a low frequency inverter will allow up to 3 times the max current as surge for a second or even longer. But such currents will still be much lower then a grid connection would cause in case of a fault. That means that normal over-current devices as MCBs or Fuses will react much slower. I have suggested a 63A contactor because it is the same build and price as for example a 32A version just with higher current tolerance. Why would you not go for the version with better contacts if it is in the same price range? Wouldn't this be helpful for longevity of the relay? True, faults do not occur frequently, so it usually will not be relevant much.
@@RolandW_DIYEnergyandMore So you want send to the inverter the maximum possible fault current from external source (via ground, in the case) via N pole when, AS AN ISLE, this could be managed ONLY by the ground (by definition infinite). This has no sense at all. Islanding in a normal grid situation is not a matter of playground for dummies, we have very stringent rule for safety and regulation. In some contries is not permitted.
@@carlorobotti5572 by your last comment I do think that you do not know anything about Earth fault loops in electrical installations. In an off-grid (island, whatever you call it system) how do you think a fault current (L shorting to the grounded case of an appliance, etc) is returning to the inverter? By the PE,G wire of course. And if you want to trip any fuse or MCB as a protective device you will need a N-PE,G bond. The current is limited by the maximum power of the inverter only as the resistance of the wires involved will be very low. In my example with my 4000W high frequency inverter, that would be around 40A for 1 sec over the N-G bond. A fuse or MCB can never be tripped by only a loop through the soil itself through rods (TT) as the currents will be far to low. That is the duty of an Residual Current Device (RCD, RCBO). Thats why you need a bond while your are off-grid, and no bond when the grid is connected. But yes, please don't play with electricity if you do not understand it.
@@Yaki-2505 correct as long you are supplied from the grid. But if you switch to inverter you should bond for many reasons which are explain in several of my videos...
Добрый день.Не могу понять... При работе от сети N соединена с трансформатором на столбе... При работе от батарей инвентор разрывает N и Вы ее соединяете при помощи контактора. Почему сразу не соединить N от сети и N после инвентора? Остается таже система TT?
This is not about N Neutral; it is about PE or Ground. In the TT system the PE loop is closed only via the Earth. But when you have your own power source like an inverter, you can only make a PE return loop via wire. Thats why we need to make a N-PE bond with the relay when operating on inverter, but have no bond when operating on transformer from the grid. I do not know the power system in your country. SO, you have to research your situation initially before making your system.
Great video, problem solved for me, thanks. I live in Portugal and we have TT systems here and here they sel this inverters for off grid use only. With this setup we will be able to use it on grid too. Thanks again.
Great news, thanks!
Very interesting subject, very informative thankyou for your time ! I recently upgraded from and standard inverter to a hybrid and came across this issue, I am currently using it Off-grid but I will hook up relay via dry contact when winter comes !! Thanks again 👍
Thank you for making the video. The inverter manufacturers/sellers did not provide much details about the Lines, Neutral, Ground.
I even ran into a comment about where to connect L1 and L2 on a device that has L1 and Neutralports only. The manufacturer replied use L1 as the first hot and Neutral as the other hot line. Well, at least there is an answer...but then what do we do with the Neutral and Ground line; I am asking because there must be a good reason why they bother using Neutral and Ground wire. This is very frustrating trying to get information!
I feel like not many actually address the wiring of L1, L2, Neutral, Ground! Some people even be making about you don't need Neutral if you are using 240v. 🤦♂️
hi. there is a simple answer. do not use inverters built for other regions, especially when there is a totally different electrical system then in yours. if you live in US system, use US L1 L2 devices. using LN devices will prohibit you from earthing that device properly when in grid connection.
the victron mutliplus internal relay also open and close the ground bound depending if it's in it's transfer mode or standalone inverter mode
but i'm still didn't make up my mind about how to install it
in beginning, i was thinking about bounding neutral to ground rod, but realized maybe i should just earth the inverter chasis, and the internal relay will do the rest
the inverter also have an independent auxiliary ground relay socket to control an external contactor
Hi Roland, I believe I have exactly the same booklet where it discusses the relay contact positions of the "Dry Contact" terminal block. I paused your video at "15:47" and compared the wording from your book to mine. It appears to be identical with the exception that the program numbers used in my book are different to yours, ie #20 and #21 for you, but I have #12 and #13. However, I believe that is semantics only, but are referencing the same settings.
There's one bit I'm not sure I follow 100% correct, and I was hoping you may have noticed this yourself, or could help me understand this better.
The table states that for the following conditions.....
Unit Status = "Power On"
Condition = "O/P is powered from Utility"
"NC & C" - Close. "NO & C" - Open
Which means that the "NO & C" contacts would be "Open". And....as you have illustrated in your video, this would remove power from the Earth Bonding relay, and consequently remove the Neutral-Earth Bond and restore the TT Earthing Technique as per Grid Supply, AKA No local Bonding 🙂 Sounds Good and appears logically correct to me.
You then go on to say at "17:04" in your video ....
"So when the machine switches over to the Off-Grid Mode the Normally Closed (NC-C) will then be open, and the Normally Open (NO-C) will be closed. And this is what we need to know....."
By definition and logic this action would then bond the Neutral and Earth for Off-grid operation, however.... now that the "Condition" of the device has changed to "O/P is powered from Battery or Solar" and we review the table, there also appears to be other conditions we need to verify to see what state the "Dry Contacts" will move into when it goes back to the "Off-Grid" mode.
Let's assume we have set Program #1 to "SBU" or "SOL". If it's a bright sunny day, and your batteries have reached full charge set by Program #21 (My Program #13), then according to the Table the "NO & C" will Open. My assumption is that the Device will still remain in Off-Grid Mode, but the Neutral Bonding to the Earth will then drop because the Relay is de-activated.
In another example which I believe would have unfavourable outcomes would be if you have Program #1 set to "UTL", and for whatever reason the Battery Voltage fulls below the threshold of the "Low DC Warning voltage". Which I can only assume would push power through from the Utility Grid Supplier. This condition appears to close the "NO & C" contact, which would re-enage the Neutral Bonding to the Earth, even though we are using Grid Power.
Not sure if I'm mis-interpreting how the "Dry Contact" NC - C - NO relay contacts work, but your advice, knowledge would be appreciated.
Hi Jeff. You are right! I have looked into the booklet and came to the conclusion that the writer or translator of that booklet didn't have his brightest day. This table is used by every single device manufacturer but cannot be right.
If the main column is separating between Output on utility or output on Battery, that it shouldn't be possible that when conditions of battery modes which require the contact to switch to utility are doing exactly the opposite of what the main statement is telling.
I will research this on my device and release a video on how to do it correctly. Just follow the instructions on the table regarding the battery mode (I am sure you want to use the inverter in Solar mode). This seems to be correct. But because the contact position will be different now, we need to use the dry contact of the Transfer switch in a daisy chain to open the bonding relay when the inverter is shut down. I will explain that in the new video...Thx
@@RolandW_DIYEnergyandMore I'm glad you came to the same conclusion I had, ie "Utter Confusion" with the table :-) ...I checked, double checked, and triple checked my theory...AND...without having my Inverter installed and powered up yet, I am unable to test it myself. I'm waiting for my EVE LFP Cells to arrive so I can construct my 48V 13Kw Battery, and in addition, I need the time to install my Solar Panels on the roof, so I'm all theory at the moment. I'd be interested to see what you come up with in comparison to what i discover with my Hybrid Inverter, when I build my system. Thanks Again.
Not 100% sure what your plan is with your "Change Over" switch, but it seems like it has a separate set of contacts (low current) that you are planning to put in series with your Off-Grid Device "Dry Contacts" to create a Boolean "AND" operation to control the Neutral-Earth Bonding.
@@jeffclarke7990 yes. The table seems to be correct. I checked it on my inverter today. Just don't really know when the basic option of "Output is powered from utility" can actually be met as you can run the inverter only from one of the 4 modes in item #01. The dry contact then is primarily controlled by the two set voltages (Batt low and Utility return) which will command the switch to the grid when in SOL, SBU or SUB mode.
As I said. I do assume you will run the device on SOL anyways, so the dry contact to be used is NC. This gives us the conflict of being in the same state as when the inverter is shut down. But for this case we can use the highly recommended ATS, which typically has a dry contact as well, to use its contact in series as you have noticed. The ATS dry contact will open when it is "changed over" either automatic (if the inverter fails) or manual (when doing maintenance, etc) and release the N-G bond.
@@jeffclarke7990 thanks for your kind donation. Keeping standards in DIY is a work in progress :)
Fantastic video, thank you
Thanks for watching :)
Hi Roland! Great video. In my US system, I am grid tied on emergency backup, my grid input panel is neutral-earth ground bonded. My 6 split phase inverters terminate on my load output panel that is not bonded, but goes to my input panel. My inverters switch the NEG bond when in DC mode. Many have recommended that I need to remove the inververter internal NEG bond. One person said I need only one inverter relay, per Viktron instructions. Appreciate your insight! -Jay
Hi. As you do have so many inverters i would say that one, but that to be an external high power bond would be preferable. Imagine if fault current powered by 6 inverters go trough an internal NEG bonding relay of a single inverter which was designed for its own power level. I wouldn't remove all bonds as then you would render all your GFCIs useless as well as MCBs which might do its job as you seem to have that extra power from the 6 inverters ;) In general inverters have their built in short circuit protections and will eventually shut down...
@@RolandW_DIYEnergyandMore thanks Roland! So to rephrase, with my supply side neutral-ground bond (NB), I can safely remove all inverter’s internal NB?
@@jcschwarb your supply side bond is not passed through the inverters when in off-grid mode (i think that is what you have called DC mode), or is it? It is right that the inverters switch a NEG bond when disconnected from the grid input, but of course if all 6 are doing that, then you get 6 different fault paths. It would be better if a single external relay is doing that job. Its hard for me as i do not know your actual setup and don't know if your inverters have a dry contact.
@@RolandW_DIYEnergyandMore Thanks again Roland. Not sure how to resolve this. Hoping the manufacturer can provide direction as I think this is their issue to fix since they are selling the solution that I am trying to configure per their manual that doesn't cover any of this topic. I am having a hard time getting both phases to run together, only phase B is working currently when I energize up to four at a time.
During testing yesterday, my no. 3 inverter had a catastrophic failure with a loud pop that caused all other inverters to shutdown immediately. Trying to understand what caused this. I only had 6 48v batteries applied. Was this possibly due to the NG bond issue?
Thanks Roland, please do more video about this topic (TT earthing system with off-grid solar inverter)
Many inverters in my place don't have dry contacts or any similar provisions! What shall we do to make our installation SAFE?
@UA-cam user, which type of inverter do you think of when you say Off-Grid without Dry contact. So, you still have an Off-Grid inverter with AC-In which you are trying to use when the Battery is flat, right? Or are you purely Off-Grid? Then you don't need to care about the Grid System around you at all. Just build your own TN-S setup as shown in one of my other videos.
As XXX is noting, the only other way is to use an Automatic Transfer Switch, which will switch over to the Secondary Source once the Inverter stops. But that switch is not seamless same in the All-in-One inverters who can switch over similar to a UPS. So, there will be a gap of 1-3 seconds depending on the model of ATS. The TT-Earthing system makes a solution quite inflexible. You have to consider the equipment which you can use there
Well explained and much appreciated, its not obvious when you buy these all in one inverter you need a ground neutral bond in battery mode, though wonder can the mentioned load center then go through a transfer switch to consumer unit on power outage ?
A transfer switch will always be à good way to create isolated circuits behind 2 different power sources. Its just important to put the N-G bond on the right place if one source must be bonded and the other doesn't.
@RolandW_DIYEnergy ok so we do not need to use the contact relay, just bound the off grid source before going into the transfer switch ? guess ?? TIA, p.s. for clarification we have similar china all in one inverter like your, and only use one socket for small loads (permanently) and only transfer on power cuts.. it is only using solar to charge grid not connected...
@@hasger1941 yes correct. If your grid is TT then just bond at the inverter before going into the transfer switch.
@@RolandW_DIYEnergyandMore ❤👍
OMG! Thanks Roland. After my last comment, I figured out that TT system is actually used in my country and I have been researching how to do this with Growatt SPF 5000 ES based on your other video. It is now crystal clear to me how I can do this on inverter's AC output side. But I do have a question for AC Input's side ground. Please let me know if I should bond the AC Input ground to load center's Ground as well.
Well, in a TT system you wouldn't have an explicit AC in Ground :) Did you ever measure, if Ground terminals for In and Out arn't actually one anyways?
@@RolandW_DIYEnergyandMore Thanks, Roland. It took me a month to figure out this complex topic. This is my latest finding so far. My inverter seems to be from a newer batch, so it does the N-G bonding internally on battery mode and breaks the bonding on grid mode. So that means I don't have to use the method mentioned in this video. I understand that the inverter on battery mode turns the system into TN-S since the AC input is disconnected and isolated internally. I measured 0.001v between N and G. In grid mode, the system becomes TT since AC input and output are connected, and I need only to connect the AC output's ground to the earth. But I found the voltage between N and G is now 10v. Is this expected "Stray Voltage", or can you enlighten what I am missing here?
@@tibuuso I'm no expert at this, nor do I have the experience that Roland has, but in a TT system I would expect that the voltage maybe straying, because the Earth to Neutral bonding is done at the Transformer, and there is a large impedance between the Supply side's Earth Rod at the Transformer Source and your local Earth Rod in the ground. I'm happy to stand corrected on this matter, but the whole subject of Earthing Families and their subsets is a fascinating subject to say the least.
What happens if the relay has a fault, i.e.: broken coil? Or the opposite, what if the relay is blocked and does not release the contact?
I mean, the grounding system is thought to be there to protect in the case of faults, adding a relay just adds up another thing that may fail.
Hi. Yes, every extra device in a circuit is another point of failure. Relays are luckily very simple and rarely failing items especially when you consider that under normal circumstances there is no current flowing over it.
If it fails to close the bond, then your system will turn into an isolated system. There is nothing bad in that scenario as long as there is no secondary isolation failure within your grounding system. You will just run the inverter as probably most other people do. Multiple grounding failures might even turn an installed RCD (which in an IT setup is useless) sensitive again as the installation is turned from IT to TN.
The DIN rail relays typically have a small indicator on them which shows the state of the contact. So, you can see if it fails to close if it should have.
If it fails to open because the contacts are stuck together, there will be an unwanted N-G bond while you are connected to the TT-Grid. If there are leakages somewhere on your transformer client's group, you will see a current flowing over your bond. These currents will typically not be high as they are just picked up by your grounding rod, as well they won't be dangerous but they will be there and cause confusion :)
Your own installation will still be safe under this condition as there is a present ground loop available for the RCD to detect faults.
Just always check your system. Everything shall be maintained. The inverter could have a similar problem if it has an integrated relay and it fails...
I. Understand why such relay is sensing the difference between Grid power and inverter powered by batteries as by norm common installations (grid power)would already have a neutral to earth bond before the consumer unit itself TN-S system. In such way that there would always be one ongoing bond of this sort at a time preventing possible transient currents and most importantly allowing the Residual current device or RCBO’s to detect unbalance current between live and neutral hence tripping and isolating the supply under leakage to earth fault condition.
May i just point out that in a complete off grid electrical installation no such relay would be necessary and one bond would be necessary at the consumer unit itself.
Great video.
I am in the UK and my house grid system is TN.
I have bought an easun hybrid inverter that has the option for the internal earth neutral bonding.
So my solar system will be offgrid with the option of using "line mode" in the inverter during the winter to charge my batteries using cheap night time electricity.
If I use the inverter internal option of earth to neutral bonding do I still need the relay using the dry contact or is it better to use the dry contact with the relay on my off grid consumer unit instead of the inverter earth to neutral bonding?
I assume if I use the inverter earth to neutral bonding then it will be connected to my house TN earthing system via the mains line mode connection.
Keep up the amazing work 👏
Hi. Is it possible to program the internal link via the inverters UI by mode or would that bond be permanent? If it is settable, then you wouldn't need an external relay. Nevertheless, the external option is the better one as you can use high current relays for bonding. The internal relay might not be powerful...
@@RolandW_DIYEnergyandMore thank you for the advice.
Great Video!
What is the situation in peak shaving mode?
That case some power coming from the solar and some in same time from the grid?
This system can use 3 input mode at same time..
- grid
- battery
- solar
Really crazy to handle earth protection by proper way.. or just must believe the Chinese engineers..😀
well...such inverters are primarily grid tied inverters which store excess energ in a battery and give it back when required. Being completely off-grid and requiring the seperate N-G bond will only happen when the grid is down, right? So you would need the bonding relay for that "Emergency Power" case only. Maybe the inverter will have a bonding relat built in already. Yes, earthing get get very complex and that was exactly why I started this videos to get discussions going and increase awareness when people DIY. Thx
Going deeper down the rabbit hole, my gosh :)
As i said in one of your previos video i have Deye Sun 6-K single phase all in one inverter.
As we comment already about my neighbourhood trsnsformer grounding system TN-S (but it appear my house have TN-C because my home DB dont have PE bus bar) and i will use additional grounding rod connected on main PE copper wire which goes in main supply DB where also my house DB connect, i hope this does not apply to me!?
I checked manual. There is no such table here, nor i have info if my inverter have internal ng bond. As per manual they state only this:
This diagram is an example for application that Neutral connects together with Protective Earth in distribution box.
Diagram say that Grid-connection port PE line connects to neutral in house DB, but backup-connection port (off-grid ups port) PE leave disconnected while backup-connection port Neutral connects to Neutral of grid-connection port which is already connected to PE line. Am i safe to forget this story about dry contacts reley connections?
I mean there is no such theme in manual as you are discussing here!
God bless you mate.
What I have read till know, I think you have misinterpreted what earthing system you have. The earthing system of your house is defined by what you have delivered into your DB.
If you get 2 wires in from your utility and somewhere right after there is a split of Neutral where your PE is born at that point and connects to the PE bar, then you have a TN-C-S as probably most other people will have.
If there is no split of utility Neutral into two, and your PE wire which connects to the PE bar is coming straight from the rod at your parking, then you have a TT system.
But in any case. The Deye SUN6K is a grid interactive Hybrid inverter. It is basically a grid-tied inverter with off-grid backup. So, you need to connect it as any other appliance in your house using L, N, PE as there is. The question is only what the N-PE status will be when the grid is down and if it will provide a N-G bond in that case or if your installation will then run isolated.
It doesn't really matter in that case. But maybe there is an internal bonding relay which can be set in the UI for the case when the inverter is off-grid.
You are good to go to just connect your inverter to the existing PE bar of your house.
@@RolandW_DIYEnergyandMore Thank you Sir. Roland for explanation. English is not my language (i am from Croatia :)) so sometime i get lost in writing sorry ;(
I will try to explain better now. Some twenty or more years ago we had electric coming from aerial poles to my house. In that time we had TN-C system of grounding and all house wires for apliances was two wires only where PE connect to neutral. Then Elektra decided to improve infrastructure, install neighborhod distribution boxes, lay down new underground cables and switched to TN-S ground system. After that, we all was connected to new system but our houses was left on two wires only and our neutral wire was connected to PE wire in these big neighbour distribution boxes. Thats why i said our grounding system is TN-S but my house appear as it is connected to TN-C system (as before improvement) becouse there is no PE bus bar in my house DB. Meanwhile new houses was built in my neighborhood with three wire laydown system ( L,N and PE) and connected to these new neighborhood distribution boxes, hence that PE copper wire on my brother parking lot and this PE copper wire is connected on PE terminal in big distri box where my house is also connected. So this is same wire my house is using but on different way.
I hope my explanation have more sense to you now :(
@@RolandW_DIYEnergyandMore Or maybe we realy have TN-C-S system. I will check later with my electrician. Its half past seven and its Sunday so i will bother him later with coffe and nagging :))
@@zoxwolf2133 hehe OK. You will see the Deye SUN6K is a very capable inverter. It will manage any earthing system well ;)
@@RolandW_DIYEnergyandMore Thank you for easing my mind Sir. Roland W. And thank you for your comment about my inverter. I hear more and more good words about Deye products. I needed that coz when i bought it i didnt know a squat about it :)
Cheers mate
Thank you for the video. I have a question?
Is it mandatory that a grid tie inverter to have a neutral AC connection?
We have a 127/220V 60 Hz TT grid
case 1:
Grid tie (not a hybrid) split phase inverter.
Is a inverter neutral AC connection mandatory and must it be connected to the grid
case 2:
Grid tie (not a hybrid) 3 phase inverter.
Is a inverter neutral AC connection mandatory and must it be connected to the grid
Thank you Andy
Without a neutral you cannot create an earth fault loop. Technically for certain types of loads a phase to phase (split phase or 3-phase) is perfectly suitable, but an inverter tied to the grid will still need to be connected the way it is designed. And that will require a Neutral and a Ground connection as well. So, by probably any national code it will be mandatory.
@@RolandW_DIYEnergyandMore thanks for your feedback
Hey Roland nur eine kleine Anregung. Wenn du diese Beiträge auf Deutsch machst we're echt super. Damit erreichest 150 Millionen Menschen
Hallo Erik. Bei Themen welche Ich denke gut in Deutsch ankommen sollten, versuche Ich es ohnehin. Nur sind bis dato meine deutschsprachigen Beiträge kaum angesehen worden.
Und bei den meisten Themen müsste Ich die ganze Zeit darauf hinweisen das in der folgenden "Dauerwerbesendung" es um Dinge geht welche "niemand nachmachen sollte oder darf" :)
Der deutschsprachige Raum hat viele talentierte UA-camr die es auch verstehen ein wenig Geld aus ihrer Aufgabe rauszuholen, dass mir eigentlich nur der etwas unterbediente Teil der (3.) Welt überblieb, damit auch die Menschen hier wenigstens einmal etwas von Sicherheit ihrer elektrischen Installation hören, oder eine Idee darüber bekommen wie sie die persönliche Versorgungssicherheit in Ihrem bemitleidenswerten Stromnetz steigern können :)
Also wie gesagt. Es kann durchaus sein, dass es hin und wieder auch Videos in deutscher Sprache geben wird. Generell ist es allerdings viel Aufwand zweisprachig zu filmen und zu schneiden...Grüße nach Deutschland, Oesterreich und Schweiz!
Vielen Dank!
The local utility in the Philippines uses TT system, the inverter is bonded.
The problem is after a typhoon the utility post very close to the house is supported now by a cable which has caused a connection between the post ground wire and neutral and its very unlikely it will be fixed, so my question is should my bonded inverter be grounded or should I unbond the inverter and ground it
Hi. What is your type of system? Hybrid with connected grid, off-grid, off-grid hybrid with grid bypass?
@@RolandW_DIYEnergyandMore Its on grid/ off grid. Solar is priority then battery and finally grid. We do not export to grid.
Nice details Roland. I bought a Solax X1-Hybrid G4 and were I live TT system is used. Excluding the DC part (PV and Battery), the inverter has L-N-PE on AC in, i tested for continuity between N-PE and there is none when the inverter is OFF with nothing connected to it. On AC out there's only L-N, my question is do I still need the relay/contactor to avoid grounding loop when I will be in "grid" mode (using AC from grid because there is no sun and battery is depleted)? From my understanding my answer would be yes but I checked and unfortunatly this inverter seems to have dry contact but It's used only to connect "SolaX Power Adapter Box" that can manage a smart heat pump, i don't think i can command an external relay from that. Thanks in advance
hi. well i guess you will need to achieve a N-PE bond if you want your system work as a grounded system same it is when it is on grid. you would just need to check what you dry contact is doing in each mode of operation. then you can see if it is similarly usable for the external relay.
Hi Roland I am having an issue where my plug and play 5kw inverter trips the earth leakage when power from the grid resumes. Any idea what can be done to prevent this.
Hi. I assume that you have installed the inverter via its AC-In downstream of an RCD. That will usually trip the RCD if the inverter is N-G bonded while on grid power is bypassed through the inverter. So you have to get your bypass grid power from a spot before the RCD or control the N-G bond actively, so that it is only present while your inverter is in off grid mode (bonding relay)
@RolandW_DIYEnergy Thank you very much for your assistance highly appreciated
so if i have 3 parallel and 1 for split do i need to connect all of the inverters to the contactor ? thanks
If all inverters are switching between off-grid mode and on-grid mode the same time, only one inverter needs to command the relay. If inverters switch differently, then put dry contacts in series so that the bonding relay will open as soon one inverter goes on grid. Please check you table on modes again about when the dry contact is in which state. We found out its more like mode dependent then simply set by bypass...
Hi, nice video.
I will be using a 3K simple pure inverter. Without AC input and only with DC input and AC output without ground.
I have an ATS connected before the differential magneto-thermal switch that when it no longer senses the AC output of the inverter it switches to the AC input of the grid.
In your opinion in this case what arrangements should I make?
If I understand correctly I should put the Neutral to Ground when the inverter is delivering AC and instead disconnect it from Ground when the inverter disconnects AC.
I could use dry contacts from the ats since the inverter does not have them!
What do you think?
Hi. You actually do not need any special bonding arrangement other than to bond directly at the inverter. The ATS is keeping the bond isolated on the inverter side anyways once it switches to grid. Just be aware to use an ATS which is disconnecting all active lines (phase and neutral)
@@RolandW_DIYEnergyandMore Yes. I have an ats that disconnects both line and neutral.
So it's enough that I connect the neutral coming into the ats from inverter with the ground so that when I have power from inverter the safeties work properly
@@VacuumInfinity yes, that is enough. It will create a return path for fault currents and cannot interfere with the grid supply.
@@RolandW_DIYEnergyandMore thank you!
Hi
Previously, I have asked you about this issue and you advised a transfer switch. Does this solution remove the need for a transfer switch?
Also why would you need the 2 pole relay instead of a single pole relay, for the N G bond?
Great content as usual !
Was this a eureka moment for you?
I only considered using the dry contact to start a generator, as the manual suggests, lol!
Hi. A transfer switch is still advisable if you need to bypass the whole inverter setup in case of a malfunction or maintenance, that is why the relays should be set up to open when the inverter is off. I was mentioning this already in the practical guidance video but was thinking more of inverters which do have a dedicated bonding relay built into the unit. Then I just noticed, that those units which we are using all come with a dry contact which can be used for the purpose as well. I am showing a 2-pole contactor, because those Din rail relays are available in 2 or 4 pole versions. But if you have a 1-pol, high current contactor, you can use that one of course. But with a 2-pole contactor, you could also bond and start a generator at the same time if you would want to do something like that :). Thanks for watching.
Hello , great job , very useful video, pls i need to know more about the relay and the link to have one
Hi, there is a link to a AliExpress shop in the description for reference. The coil of the contactor is switched by mains voltage through the dry contact. That's how you can switch a 63A relay with a 3A contact. You just need to choose the relay type with AC 220V coil.
One more thing pls , how to wire the dry contact no/c to the relay 1-2-a1-a2 ?
I think 1 to the pe bus bar and 2 to the rcd in, a1 to the no and a2 to nutral bus bar. Is that correct ? Advice me pls
And tx in advance.
Yes, that is correct.
Much appreciated ,,
Hi, I have connected a stand alone system with a MUST PV1800 inverter. The system came complete with inverter and circuit breakers in the panel for the solar, battery and 230 volt output. The 230 volt powers a tiny house which has and RCD on the switchboard. If I connect neutral to earth the inverter detects a fault and shuts down with an fault code 03. According to the manual this is "battery voltage too high" but that makes no sense - the battery voltage is no different without an N-E connection. Without the Neutral to Earth bond the RCD doesn't work. Any ideas..?
hi. this makes no sense indeed. is the battery grounded at the case or even at one of the DC poles? if yes, remove ground link there.
I have a MUST Hybrid Inverter as well. It doesnt have N-G bond inside... My Earthing system is a TN-C-S one and my inverter is using this very same earth system, but when in off-grid mode, on battery power, there is a voltage measured between N and G on the power outlets, something more then 100 volts for a 220/230V output. Is it normal? Do I have to bond N/G again after the inverter when in off-grid state?
Hi. Yes, you have to make a N-G connection. You can as well use a relay to bond only when in Off-grid mode, but in TN-C-S net, you might as well keep a permanent bond behind the inverter in you load center. Typically it will not interfere with the grid grounding in such a net. I have it that way in my system.
@@RolandW_DIYEnergyandMore Okay! Thanks for the information!
Hi Ronal, I have a problem with the UPS connected to the PC.
Let me explain: if I switch to SOL mode everything works. However if I use SBU mode the ups starts to trip as if there is no voltage.
I ask everyone if anyone has my problem and has solved it.
Greetings from Naples.
Hi. I just compared the SOL to the SBU mode and there is nearly no difference (only some timer-based options). At least not in how the inverter provides power. Why can't you use the SOL mode as your mode of choice if everything is working there?
I cannot explain why a UPS is working on one mode but not the other. Each mode is providing AC to your house.
@@RolandW_DIYEnergyandMore Unfortunately this is the case. I repeat, if I set SOL mode, turn on the printer, hairdryer or coffee machine I don't hear the surges on the ups.
If on the other hand, and I can't explain this, I set the ups in SUB mode whether it turns something on or not, it jolts.
Hello again, i was trying to connect the relay the way u told us to do, i have a Growatt 5000 es, i checked for continuity between ground and neutral at the AC out and it was bonded. Before i unbond neutral and ground inside the inverter , i checked for the continuity between the same neutral and ground when the inverter is on grid , there was no continuity between them . So i think for this all in one offgrid inverter there is no need for unbonding neutral and ground from inside the inverter and using this relay, pls check and advice if im wrong, and thanks again for ur helpful topic and ur advice. Waiting for ur reply asap coz i was about to install the relay .
Hi. OK, if that is sure that the internal N-G link is behaving similarly as I am describing the function of the external bonding relay, then the Growatt ES is providing an internal relay already and there is no need for this external modification. Did you also check if the link is open when the inverter is turned off?
Later this year, I will demonstrate an extended functionality of an external solution by also daisy-chaining an automatic transfer switch into the control circuit. That might then be another reason to remove the internal link. But as far I see now you are good with that inverter using it in the TT-Grid.
@@RolandW_DIYEnergyandMore
Hi,thx for being helpful , actually i did not check before for N-G bonding when the inverter is turned off, but now i checked it, and it was bonded when the inverter is turned off. But thinking is that a problem ?
Waiting for ur next demonstration 😍😍
Keep walking GOOD LUCK
@@rabihghannoum1198, probably there is no problem because I think that the inverter when Off will surely not bypass to the Grid and the AC Output will just be powerless.
Great video!!I am going to install growatt 5000 es in Bangladesh, also have TT system. Looking at your diagram you have a separate grounding for inverter. Will it conflict with ac in port which will have currently installed house grounding ?
There is no separate grounding for the inverter. It is connected to the house grounding. The TT-system doesn't provide an utility ground for the AC-In. That is the reason why we need to use the bonding relay to provide grounding link in Off-Grid and disable when On-Grid. Be aware, that the Growatt 5000 is known to come with an internal N-G bond in some countries. If you find your N and G terminal having continuity, then the internal bonding screw needs to be removed for the TT-system. You can watch some US YT channels which are covering that story.
@@RolandW_DIYEnergyandMore I have purchased this inverter from a US authorized supplier (internally modified) and checked the continuity with volt multimeter to confirm there is no bond between N & G. I have also purchased the relay as you instructed. Thank you .
@@user-yp9cc8wr8x great, then there is nothing to say about it :)
my system is hybrid with grid connection but no export.
A Grid-interactive hybrid inverter in his normal mode, is equal to a grid-tied inverter. It doesn't matter if you export or use an export limiter. So it will use the grounding system provided by the grid. Only when it switches into off-grid mode when the grid is not available, you would have to provide a N-G bond. Maybe your inverter does have a relay signal to do this, or even has an internal bonding relay? What is your inverter?
Its a 6kw Powmr hybrid imverte
Thanks for your help
I dont agree on using a big relay current (63A?) fo the Ground-N bonding justified by the fault ground current from the neighborough premises.
On the contrary the G-N bonding is by definition a Zero current bonding in normal operation WITH battery (Isle system) and fault current must/can be avoided by a normal low Amp FUSE together with a low current relay. The lost of the G-N link must not be a problem with majority of the appliances, only few of them are (without damage) sensitive
Fault currents caused by L-G faults are high current by nature. In an islanding system they will typically be restricted by the surge capability of the inverter. For example a low frequency inverter will allow up to 3 times the max current as surge for a second or even longer. But such currents will still be much lower then a grid connection would cause in case of a fault. That means that normal over-current devices as MCBs or Fuses will react much slower.
I have suggested a 63A contactor because it is the same build and price as for example a 32A version just with higher current tolerance. Why would you not go for the version with better contacts if it is in the same price range? Wouldn't this be helpful for longevity of the relay? True, faults do not occur frequently, so it usually will not be relevant much.
@@RolandW_DIYEnergyandMore So you want send to the inverter the maximum possible fault current from external source (via ground, in the case) via N pole when, AS AN ISLE, this could be managed ONLY by the ground (by definition infinite).
This has no sense at all.
Islanding in a normal grid situation is not a matter of playground for dummies, we have very stringent rule for safety and regulation.
In some contries is not permitted.
@@carlorobotti5572 by your last comment I do think that you do not know anything about Earth fault loops in electrical installations. In an off-grid (island, whatever you call it system) how do you think a fault current (L shorting to the grounded case of an appliance, etc) is returning to the inverter? By the PE,G wire of course. And if you want to trip any fuse or MCB as a protective device you will need a N-PE,G bond. The current is limited by the maximum power of the inverter only as the resistance of the wires involved will be very low. In my example with my 4000W high frequency inverter, that would be around 40A for 1 sec over the N-G bond. A fuse or MCB can never be tripped by only a loop through the soil itself through rods (TT) as the currents will be far to low. That is the duty of an Residual Current Device (RCD, RCBO).
Thats why you need a bond while your are off-grid, and no bond when the grid is connected.
But yes, please don't play with electricity if you do not understand it.
Or the serial number of the relay pls
No bonding in TT systems!!!
@@Yaki-2505 correct as long you are supplied from the grid. But if you switch to inverter you should bond for many reasons which are explain in several of my videos...
Добрый день.Не могу понять...
При работе от сети N соединена с трансформатором на столбе...
При работе от батарей инвентор разрывает N и Вы ее соединяете при помощи контактора.
Почему сразу не соединить N от сети и N после инвентора?
Остается таже система TT?
This is not about N Neutral; it is about PE or Ground. In the TT system the PE loop is closed only via the Earth. But when you have your own power source like an inverter, you can only make a PE return loop via wire.
Thats why we need to make a N-PE bond with the relay when operating on inverter, but have no bond when operating on transformer from the grid.
I do not know the power system in your country. SO, you have to research your situation initially before making your system.