The best part of the software is (34:52 etc.) how the right justified voltage reading jumps back and forth depending on whether the 4 decimal is a zero (and blanked) or not. LOL... nice programming.
The 8500 serial port is TTL levels, the 8601 is RS232, as shown on the equipment back panel. The 8500 isolated USB to TTL adapter (model IT-E132) would not work. It would be nice if the unit would just detect when something is connected to the port and enable it.
Granted that linux would not run any of the provided software, but it is really easy to write short programs using SCPI, and USBTMC drivers are usually included by default.
Aint the LED mode in these programable loads intended for the driver cirquit? 5:58 // it does look like the manual your showing emphasize it is a LED-driver optimised mode.
The built in rise and fall measurement could be useful in some automated pass fail test for power supplies where the waveform has been validated previously in the design phase and wouldn't change in production.
The RS232 didn't work because you have to manually go to device manager, find the usb-to-serial adapter and change the com port in advanced port settings to one in the drop down of the software. It seems that the software sometimes only looks on certain com ports for communication and doesn't search for usb to serial on other com ports. I had this issue with my BK 1788 power supply.
Do yuou really want such screw fitted terminals when we are dealing with a high precision 60A load 11:27 versus a wellsoldered connection on some high gauge quality silicone wires.
Being able to replicate different forward voltages of LED load is good for testing Led constant current drivers over their whole output range. The load I use for work is especially different from an actual LED at low current.
Never did understand this silly aversion to reading manuals. Personally, I really enjoy reading them and really getting to know the ins and outs of the thing I bought that I may otherwise miss out on, knowing I am operating it in an optimal way and just getting to know my new toy. Sure, I might get that some people don't have that patience, it's fine. But when it goes to a level where you are seriously frustrated and raging about it, it's really time to learn that if you can't get something to work how you want it to, the first thing to do is generally consulting the manual. It's also amazing how an accomplished electronics engineer like Dave is generally so inept when it comes to software. Sure, I have only seen some pretty simple arduino stuff I think he wrote, but just observing him operaring and talking about software make one seriously question his grip on the subject. Personally, my experience is that many electrical engineers make excellent programmers. In the case of Dave it has to be noted tough that this slight lack of provess in one area is quite made up for by his knowledge about electronics design, especially analog such, and not the least, his one of a kind personality. My wife watched a vide over my shoulder a while ago and though it was actually some kind of joke video saying no one can honestly be excited enough start moaning and go into a falsetto when talking about electronics. comparing him (quite accurately) to Bear Grylls (spelling?).
I know they won't release a service manual for it, since they even scratched out the part number of 2 or more ICs. I am curious to know how they manage to make an analog load out of switching MOSFETs without seeing the schematic?
Unless the load input is grounded (which would be a problem in itself) that mains connection with only basic insulation to the input terminals does not comply with most safety standards.
Why does it have the fluorescent display? Doesn't that just add extra cost and complexity? Does it have a practical function or is it a bit like having vacuum tubes in your stereo? Some people just prefer it for the look and feel of it and are willing to pay extra and accept the drawbacks like burnout.
+EEVblog yea, software its getting really heavy, as a computer engineer I can tell it is just for being beautiful, most of the weight in software it is not the program (which usually its never more than a few mb), the weight comes from the resources (images, sounds, animations, objects, etc)
Elliott's Tech Show is my 2nd UA-cam channel. I am in the UK, I get around 35-40Mbps Dwn & 5-7 Mbps Up; and have unlimited data. Callum Hatch That 4.3TB usage was from my normal web browsing plus regular uploading and downloading to and from my 1&1 hosted server. At the time I was also streaming a IP cam to my 1&1 server 24/7 during the month of December. EEVblog Dave, how much your data limit per month at your lab and also at home?
I know this isn't cool, but read the manual! If, like most people (including myself sometimes), you don't want to read it, that's fine, but then don't complain when you have to figure out why it isn't working. I am surprised that the BNC current output is referenced to the negative input terminal, instead of chassis ground. If you were testing a negative supply which had positive grounded, you would short the supply by connecting the BNC to a scope.
This right here! Building a load tester myself and because I don't have any way to drive a MOSFET down to 1mV increments, my options are an IGBT (don't like heat though) or a whole buttload of resistors in parallel with a relay to open/break the circuit when needed.
Dave, The Itech versions are available with the new 2 line display. The equivalent range to the BK 8600 seem to be the ITECH IT8800 series. I haven't dug into the datasheets, but it looks like the IT8812C is the equivalent to the BK 8601. That isn't to say the BK isn't worth the extra cost if you want the service, especially if you are talking about using the instrument in a business environment. For the home gamer it doesn't matter quite as much. The ITECH IT8500+ (the + being the important part) also seems to have the 2 line display, although the digits are the 14 segment style, not the dot matrix style. But the IT8500+ series has models that will do 600W in the same form factor, so for someone who regularly deals in high power stuff but still wants a small footprint it can have its advantages.
Yeah the mains cable is draped across sharp edged aluminium heat sinks. Even if they whacked a couple of posts in and cable tied to that it would be better.
Excellent video Dave, as always, I have to say that it would be interesting to see you do a tear down of one of the cheaper imitation units available on sites such as Ebay, It would be interesting to see how closely the genuine article has been reproduced. P.S. keep up the fantastic work matey !!
Like the Rigol power supply, I don't think I would buy one of these because of the part numbers being scratched off the chips. Makes things more difficult to replace/work on it if and when it fails. Design looks OK, so why do they feel the need to obscure the parts?
Maybe, but if someone was intent on copying it, they would spend the thousand bucks to "peel" the chip to see what it was. Most dice have the part number and manufacture listed on them so ultimately scratching the numbers doesn't help much.
I've been looking at the BK 8600 series for my job, but the 500V maximum voltage was a bit too tight for us. We ended up going for an 800V 2.1kW H&H PLI2108 which arived today. New toy day is a good lab day :)
I recently (Nov. 2020) purchased an 8601 and WOO HOO!, the front-panel INPUT terminals have been redesigned to provide built-in 4mm banana jacks. The plastic knobs on the INPUT terminals are the same shape and size as the original, but they now have a 4 mm banana jack in the center (compared to the solid, threaded stud terminal on previous units), and the banana jacks (not the entire knob) are color-coded with red for the positive input and black for the negative input. FWIW, I live in the U.S., I purchased the unit from Newark Electronics, and the serial number on this unit indicates(?) it was manufactured in 2020: 435F20xxx. FWIW, B&K Precision's documentation for this item apparently has not been revised to show these redesigned input terminals; this is probably a deliberate decision on their part, to reduce customer service complaints. FWIW2, as of Dec. 6, 2020, this webpage for B&K Precision's 8501B shows the redesigned INPUT terminals that are on my 8601. www.bkprecision.com/products/dc-electronic-loads/8510B-8510b-600-w-programmable-dc-electronic-load.html
A bit late probably, but since I've seen these terminals I've been trying to find out where to buy them. but they seem to be non-existent to the point where I started to wonder if the pictures are photoshopped...
I don't know Dave. I've got an el- cheapo Array 3700 that even reads out in watts. I figure by the time you get to equipping your lab with this thing you already have a decent scope and bench meter, so a lot of what you get in this is just extras that we are paying for, how many bells and whistles do we need? Yeah I can't test batteries as well with my Array but I can program it to do 95% of what most people need. And all new stuff is coming out with OLED displays, that old VFL stuff is really getting dated if you ask me. Thanks for the review, B&K isn't my favorite anyway, didn't you have a piece of their equipment fail on you? Was it their 8500? Best, Rob
+EEVblog Dave, I'm prolly showing my ignorance here since I'm a repair tech, not a design engineer, but it occurred to me that this is a resistive load but with PWM, inductive and capacitive loads cause huge (ringing) headaches. Any thoughts?
I think it's a bad design. I would simply do a 2 stage high frequency SMPS and feed the power into the grid. If you wanted to really show off it could be a resonant 1MHz topology. And why have those huge bolts when you are connecting to the PCB anyway.
+Mystickneon thermal paste always winns...but these silicone (presumably) are much easier to handle and also they could be handeled via a pick&place machine....
So they just use labview to make this application, and generate exe from that. It should be able to make it on visual basic, i mean, one person could do that in few weeks. I guess they don't have chart painting add-on like SciChart
interesting design. redesign. The STM32 is a good choice, the advance timers would probably be used for doing precision timing calculation, rise, fall, ect.. They went from a Sigma Delta ADC Sigma Delta AD7708 to a SAR ADC AD7682, for speed. The older AD7708 is very slow. The software still sucks, for that price they should fix it or redesign it, they use labView components and just drag and drop those components on the window.They should follow keysight they used WPF.
Hmm, SCPI is a very simple human readable protocol over a serial cable in this case. I wonder why even bother with 600mb of visa? Why can't the app just do what it needs to do by just opening a serial port?
Why can't it export to Excel!?!?! Proceeds to open up libreoffice, i'm assuming you don't have Excel installed... FYI, those control programs are just all Labview based, so if you have issue with some of the UI it might be because of that. Not to say they made the programs well just that they only used Labview which isn't the most flexible thing in the world.
+natan keddem I expected it to export to a standard .CSV file, or an Excel file which any spreadsheet program can load. Why should excel have to be installed to do this?
+EEVblog That right click menu you got was a built in function in Labview, for that "chart" display ui element. They should have probably created some additional displayed ui control elements for exporting that data in more varied and easier ways. They can't change that right click menu easily since it is a hard coded into Labview Like I said they could have probably made a better program but they made something quick. Anyone with a half decent grasp of Labview probably made that thing in under 2 days. They needed something quick and dirty, you are looking for well done and polished.
You actually need to have Microsoft Excel installed for the export function to work... It doesn't have a proper built in generator for excel files... Basically hands off the data to excel.exe to create the file... At least thats how the old one used to work. (saw you have LibreOffice installed, won't cut the mustard for this, but you shouldn't need excel to export ffs...)
That's wacky they disable the USB connection unless you specifically turn it on. It can't be a security feature since there's no password protection on communications. Maybe they don't know how to detect a circuit's been completed. Or maybe they heard network equipment does the same thing and they didn't know it's a security feature. Also, lol at the 650 megabyte USB drivers. I thought HP has massive drivers for their printers but this is a new one. Dell combo packs that contain drivers for all possible hardware for each computer model barely breaks that. On the export to Excel thing, since it doesn't export to a spreadsheet format it probably uses an Excel plugin to export it because they're incompetent and think Excel is the only spreadsheet program in the world. It probably just gives you the same information as the tab separated text too.
+EEVblog Perhaps internally there a single serial input and the menu selection switches that serial connection between the three inputs from the back panel.
why still those displays... they consume in time then they are custom made in 5 years you cannot find them annymore... why not putting a nice color dysplay like a 4 inch or 2 4 inch displays...
What's up with your slogan "Don't turn it on, take it apart" Dave? You should always turn it on first, take it apart, and then turn it on again. This way you know if it actually worked before you started screwing with it. I think there is only one GPIB controller chip manufacturer left these days ... Btw, nice review.
The software industry has not moved on from the 1960s. Just imagine if everytime you wanted to design some equipment and you had to design an op amp from scratch and implement it in discrete components. I have this argument with developers at work. Every couple of years they produce the same applications over and over doing everything from scratch. Drives me nuts when good hardware is always let down by a massive software fail.
Must be nice to have all this stuff given to you. I am a disabled EE currently trying to survive and learn more and can't even get used things donated or discounted to me.
> _Paste into Excel.._ > Uses LibreOffice Calc Props for showing stuff working on open-source software, but calling it *Excel* just because it's a spreadsheet program? That's just like if I was looking at a copy of Fedora and assuming it was Debian because it's Linux.
On these "wimpy little to220" transistors I can dissipate 200W. Its the power of sup57n20 soldered to IHS of CPU directly by thermal pad. Nothing like that IRFP250N rubbish xD
+Arek R. TO-220 doesn't have 1) The die size capable of handling "continuous currents" as the silicon channel is too small and will end up burning/melting, also the metal tab of a TO-220 is thin 2) The IRFP260/250 is cheap, its got huge thermal mass compared to a a TO-220 and most important the RDS parameter is the main point here... what TO-220 has a RDS on of ~0.08ohms at +/-200watts max with good thermal mass? Note here the mosfet is used in the ohmic region NOT saturation (as a switch as most people use them as). The 0.05ohm power resistors will help force current share between the fets,this is to help with the varying mosfet(s) rds(on) resistance with temperature, fixed 0.05 + 0.08 ohm + rds(on) will help force current share, each fet can withstand 190w, however its assumed it is used in its saturation region (as a pulse switch), so SOA data will be at the given, however in this case its used in its ohmic region so the SOA for each is NOT 190watt each and calculated based on the instruments V/I parameters... so a 150watt e-load instrument with 4 fets will be 150/4 = 37.4 max watts per transistor which is the SOA (in the linear/ohmic region) so a 200W wimpy mosfet will fail as no SOA parameters has been addressed.
Nope, I know these things, I made few years ago 1,3kW dummy load, 10 in parallel, 0R13 resistors for equal current. I choosed these sup57n20 in to220 because they had good SOA for DC. That mosfet have rdson of 33mR at 10Vgs. But anyway in our use that resistance is not important, because in most cases it will be working as variable resistor. 200W at 15V is in SOA, they dont burn, with 0r13 resistor it can handle 250W
+Arek R its hard to justify your statement, power delivery is proportional to temperature as well (25 *c is not the temperature a e-load works at its 3 or 4 times higher 75 or 80 depending on the heat-sinking used. ) , 250w a single mosfet? no this may work but it will die in the long run, their is a reason why 10 mosfets are used for 250 watts, each only dissipates 25watts under full load (this is SOA + 10% marginal worse case safety). a 1.3k design will die with only 10 as each will use 1.3/10 = 130watts each. there is a BIG different between pulse switching loads 130watts AND continuous 130watts.. Your design is not reliable for the claimed sink figure of 1.3Kw for prolong periods. By the way, I am designing one too but im busy with the firmware, look at my channel for a preview.I have knowledge with mosfets working with switch mode power supplies in its switching region, but this is a linear mode design, the power parameters are way different.
My dummy load was working about 3 years w/o any problems but then was killed by 300VAC spikes from damaged smps. Another guy have same DL and it works about 6 years. I now going to build new DL, with digital control, something like these from bk precision.
Classic Dave... Rages about not working software because he didn't read the manual. I bet everything was explained in the manual. It is okay to read manuals... Usually with Dave the problems start with user not reading the documentation and then the frustration makes it worse. Oh well we kinda expect that from you. ;) Nice video anyways :)
+Hene193 The thing is, what he expects is quite reasonable: - why would you have to turn interfaces on? - why are other tabs grayed out when you're recording? - why it needs excel installed instead of just saving as xls? And so on...
***** It's matter of perspective. Maybe there is a reason why only one interface can be turned on at the time. RS232 is widely used in printers and industrial systems. That is most likely why it's the default. But for other things you are right. That other tabs grayed out is just stupid and favouring excel makes kinda sense since this is designed to be used in industry and usually companies run Office. But I don't think that is an excuse for bad design.
+RicoElectrico - Its not that uncommon to multiplex some outputs (at least in industrial equipment), especially when they both represent serial output which you are unlikely to use at the same time. That way you might get away with a smaller processor with less IO or you can at least skip the constant polling part. According to the picture he put in in post, the chip seems to have a native USB interface though.. which means they would need to do the RS232 by a separate chip. Makes me wonder if they bothered with the processor's USB stack or if they used an external one they were familiar with. - weird design choice of the software indeed.. - probably because they used the/an excel API because they didn't want to be subject to the whims of the latest file format changes of Microsoft. Since he doesn't have MS excel installed, the API doesn't load. In the end the clipboard export does the same. Not pretty but depending how "serious" the software is I can understand it. The software seems rather simplistic and more there to provide basic functionality, so by my guess they probably weren't throwing hardcore software developers at the project and relied heavily on what was easily doable within their tool chain.
+RicoElectrico He used excel, it doesn't require it, the data is in a tablular form, kinda akin to a CSV, except this is a TSV, which is perfectly fine. As for why the buttons are greyed out, probably something for saftey or something, really this isn't a big deal for most people since they wont have their computer so far away when testing, how he even got it that far over USB I don't even know, thats longer than USB cables should be run
+James Hyde it exports raw data, CSV would be just fine, no need for Excel native file format, it's just laziness, like everything else about the software the UX is horrible, seriously
Jesus, why those guys don't use Wi-Fi, Bluetooth or something that makes sense for this decade. I understand the legacy. A decent lab requires a lot of money, but at least some videos or resumed instructions. Is that difficult to switch automatically to the proper USB setup? At least blinking something on instrument screen. like: hey, would you like to setup your USB link?
+Thiago Coura Wireless just isn't needed in a lab environment, and sometimes you don't want your test gear to be RF sources. The problem is Dave (like many people) didn't read the manual. It makes sense that you have to tell the instrument which interface to use. A blinking "would you like to set up your USB" would be very annoying if you weren't planning on using USB.
+Chris W I agree with your point about the RF interference. I didn't thought about that, but I disagree that if you deliberate connect a USB cable from the instrument to computer a message or blinking light is something annoying. It's a temporary message to guide you. My point regarding the user experience is not to prohibit you to make thinks in a different way, but if you do, provide the hints to guide the user
The best part of the software is (34:52 etc.) how the right justified voltage reading jumps back and forth depending on whether the 4 decimal is a zero (and blanked) or not. LOL... nice programming.
+ElmerFuddGun AND the time scale below! Look at it! "Interval 0 seconds" makes it go bonkers :D
+BavarianMonkey - Yep. And 600+ MB of software for that? At a maximum of 1 sample per second (by the looks of it) I'm not impressed.
The 8500 serial port is TTL levels, the 8601 is RS232, as shown on the equipment back panel. The 8500 isolated USB to TTL adapter (model IT-E132) would not work.
It would be nice if the unit would just detect when something is connected to the port and enable it.
In minute 2:41 Dave is showing output connector, how this is called when I want to get this from store?
Granted that linux would not run any of the provided software, but it is really easy to write short programs using SCPI, and USBTMC drivers are usually included by default.
Using the RS232 port and WINE, it may actually load. I've used wine with rs232 devices and it will work.
Was the solder joint on the right power transistor's drain as bad as it looks in the video? 12:10 It looks like it's barely soldered in at all...
Aint the LED mode in these programable loads intended for the driver cirquit? 5:58
// it does look like the manual your showing emphasize it is a LED-driver optimised mode.
thanks for all the great videos Dave!
If you have the ear of B&K, and you have the interest to do the review, please offer to review their 9801 AC source.
The built in rise and fall measurement could be useful in some automated pass fail test for power supplies where the waveform has been validated previously in the design phase and wouldn't change in production.
The RS232 didn't work because you have to manually go to device manager, find the usb-to-serial adapter and change the com port in advanced port settings to one in the drop down of the software. It seems that the software sometimes only looks on certain com ports for communication and doesn't search for usb to serial on other com ports. I had this issue with my BK 1788 power supply.
I was wondering do you have a B and K 1823a that you have reviewed? I'm trying to get a feel for if it will work for my needs
Doesn't the rise/fall work from the device if you were to press shift+period (Trig)?
The autoscale reset possible every time a new sample are added. Works first after it has stopped.
Do yuou really want such screw fitted terminals when we are dealing with a high precision 60A load 11:27 versus a wellsoldered connection on some high gauge quality silicone wires.
Being able to replicate different forward voltages of LED load is good for testing Led constant current drivers over their whole output range. The load I use for work is especially different from an actual LED at low current.
+EEVblog: Could you do more fundamental videos? Or videos where you prepare something for production?
How they solved MOSFET thermal runaway power resistor problem? Older unit has those huge resistors new one looks like do not.
the led mode is for testing power supplies without risking expensive LED dies. also you won't go blind.
Never did understand this silly aversion to reading manuals. Personally, I really enjoy reading them and really getting to know the ins and outs of the thing I bought that I may otherwise miss out on, knowing I am operating it in an optimal way and just getting to know my new toy. Sure, I might get that some people don't have that patience, it's fine. But when it goes to a level where you are seriously frustrated and raging about it, it's really time to learn that if you can't get something to work how you want it to, the first thing to do is generally consulting the manual.
It's also amazing how an accomplished electronics engineer like Dave is generally so inept when it comes to software. Sure, I have only seen some pretty simple arduino stuff I think he wrote, but just observing him operaring and talking about software make one seriously question his grip on the subject. Personally, my experience is that many electrical engineers make excellent programmers.
In the case of Dave it has to be noted tough that this slight lack of provess in one area is quite made up for by his knowledge about electronics design, especially analog such, and not the least, his one of a kind personality. My wife watched a vide over my shoulder a while ago and though it was actually some kind of joke video saying no one can honestly be excited enough start moaning and go into a falsetto when talking about electronics. comparing him (quite accurately) to Bear Grylls (spelling?).
I know they won't release a service manual for it, since they even scratched out the part number of 2 or more ICs.
I am curious to know how they manage to make an analog load out of switching MOSFETs without seeing the schematic?
Unless the load input is grounded (which would be a problem in itself) that mains connection with only basic insulation to the input terminals does not comply with most safety standards.
Why does it have the fluorescent display? Doesn't that just add extra cost and complexity? Does it have a practical function or is it a bit like having vacuum tubes in your stereo? Some people just prefer it for the look and feel of it and are willing to pay extra and accept the drawbacks like burnout.
+EEVblog 600MB download is nothing compared to the 65GB Download for GTA V that I had to do the other day.
+Elliott Veares WTF!? That would blow my monthly quota.
+EEVblog yea, software its getting really heavy, as a computer engineer I can tell it is just for being beautiful, most of the weight in software it is not the program (which usually its never more than a few mb), the weight comes from the resources (images, sounds, animations, objects, etc)
+Elliott's Tech Show what the hell where u doing?
+Elliott Veares in the UK we get 50MB speed and unlimited downloads. i did use to use there 100mb but they could never keep a constant speed
Elliott's Tech Show is my 2nd UA-cam channel.
I am in the UK, I get around 35-40Mbps Dwn & 5-7 Mbps Up; and have unlimited data.
Callum Hatch That 4.3TB usage was from my normal web browsing plus regular uploading and downloading to and from my 1&1 hosted server. At the time I was also streaming a IP cam to my 1&1 server 24/7 during the month of December.
EEVblog Dave, how much your data limit per month at your lab and also at home?
I know this isn't cool, but read the manual! If, like most people (including myself sometimes), you don't want to read it, that's fine, but then don't complain when you have to figure out why it isn't working.
I am surprised that the BNC current output is referenced to the negative input terminal, instead of chassis ground. If you were testing a negative supply which had positive grounded, you would short the supply by connecting the BNC to a scope.
Hello, are you able to test a solar mppt controller with this load box in place of the battery?
I was thinking the same thing! Love to know if this is possible by setting to CV mode on this and then letting the MPPT controller adjust the amps.
...and i'm just sitting here, putting resistors in parallel...
This right here! Building a load tester myself and because I don't have any way to drive a MOSFET down to 1mV increments, my options are an IGBT (don't like heat though) or a whole buttload of resistors in parallel with a relay to open/break the circuit when needed.
@@friendlyfiregaming4601 lm324+mcp4725+ina226, test it with own arduino code and resolution is 0.01A, well it is good enought for hobby :)
Dave,
The Itech versions are available with the new 2 line display. The equivalent range to the BK 8600 seem to be the ITECH IT8800 series. I haven't dug into the datasheets, but it looks like the IT8812C is the equivalent to the BK 8601. That isn't to say the BK isn't worth the extra cost if you want the service, especially if you are talking about using the instrument in a business environment. For the home gamer it doesn't matter quite as much.
The ITECH IT8500+ (the + being the important part) also seems to have the 2 line display, although the digits are the 14 segment style, not the dot matrix style. But the IT8500+ series has models that will do 600W in the same form factor, so for someone who regularly deals in high power stuff but still wants a small footprint it can have its advantages.
Guessed I missed something but why are transistors loads and not resistors used instead??
+MatthewSuffidy The transistors are basically resistors whose value you can control dynamically.
Yeah the mains cable is draped across sharp edged aluminium heat sinks. Even if they whacked a couple of posts in and cable tied to that it would be better.
Have you programed with LabVIEW? It doesn't like working sometimes..
Can we get some (high quality) pics of the teardown?
Can it be they limited the software to sell more rack-mounted unit?
would it be impertinent to ask for the surplus one if you aren't using it ...........? :)
what value are the green ballast resistors on each transistor? and what does the green body signify?
How're you getting the USB connection halfway across your workshop? Isn't the max USB cable length ~5 meters?
Excellent video Dave, as always, I have to say that it would be interesting to see you do a tear down of one of the cheaper imitation units available on sites such as Ebay, It would be interesting to see how closely the genuine article has been reproduced.
P.S. keep up the fantastic work matey !!
Like the Rigol power supply, I don't think I would buy one of these because of the part numbers being scratched off the chips. Makes things more difficult to replace/work on it if and when it fails. Design looks OK, so why do they feel the need to obscure the parts?
That is frustrating....
+kevtris It's ridiculous.
I don't know. They scratch to avoid China to copy or to repair? yeah, sadly I guess the second option
Maybe, but if someone was intent on copying it, they would spend the thousand bucks to "peel" the chip to see what it was. Most dice have the part number and manufacture listed on them so ultimately scratching the numbers doesn't help much.
Not at all. You can guess easily by the function in the pcb board, sorting vendors and removing chemically to uncover the die.
I've been looking at the BK 8600 series for my job, but the 500V maximum voltage was a bit too tight for us. We ended up going for an 800V 2.1kW H&H PLI2108 which arived today. New toy day is a good lab day :)
I recently (Nov. 2020) purchased an 8601 and WOO HOO!, the front-panel INPUT terminals have been redesigned to provide built-in 4mm banana jacks. The plastic knobs on the INPUT terminals are the same shape and size as the original, but they now have a 4 mm banana jack in the center (compared to the solid, threaded stud terminal on previous units), and the banana jacks (not the entire knob) are color-coded with red for the positive input and black for the negative input. FWIW, I live in the U.S., I purchased the unit from Newark Electronics, and the serial number on this unit indicates(?) it was manufactured in 2020: 435F20xxx. FWIW, B&K Precision's documentation for this item apparently has not been revised to show these redesigned input terminals; this is probably a deliberate decision on their part, to reduce customer service complaints. FWIW2, as of Dec. 6, 2020, this webpage for B&K Precision's 8501B shows the redesigned INPUT terminals that are on my 8601. www.bkprecision.com/products/dc-electronic-loads/8510B-8510b-600-w-programmable-dc-electronic-load.html
A bit late probably, but since I've seen these terminals I've been trying to find out where to buy them. but they seem to be non-existent to the point where I started to wonder if the pictures are photoshopped...
Dave, how do you manage to get the datasheets of dodgy/obscure components like you've done in the past?
I don't know Dave. I've got an el- cheapo Array 3700 that even reads out in watts. I figure by the time you get to equipping your lab with this thing you already have a decent scope and bench meter, so a lot of what you get in this is just extras that we are paying for, how many bells and whistles do we need?
Yeah I can't test batteries as well with my Array but I can program it to do 95% of what most people need. And all new stuff is coming out with OLED displays, that old VFL stuff is really getting dated if you ask me.
Thanks for the review, B&K isn't my favorite anyway, didn't you have a piece of their equipment fail on you? Was it their 8500?
Best,
Rob
+EEVblog Dave, I'm prolly showing my ignorance here since I'm a repair tech, not a design engineer, but it occurred to me that this is a resistive load but with PWM, inductive and capacitive loads cause huge (ringing) headaches. Any thoughts?
+Steve Brace Nothings beats the actual product under test for a load, but dummy loads like this are very useful for characterisation.
I think it's a bad design.
I would simply do a 2 stage high frequency SMPS and feed the power into the grid.
If you wanted to really show off it could be a resonant 1MHz topology.
And why have those huge bolts when you are connecting to the PCB anyway.
Sage Edwards 13:32 We need to get the Electrig in tip top shape before we send it into Dave for a review. 15:46
13:46 that mains cable is fine, but it should been wrapped in another layer of insulation really
Few days ago I had to download 120MB driver. Doesn't seem that much, right? But it was for a damn PS2 touchpad!
maybe i spent too much time in power generation but do a lot of ene users really need .1mv acuity?
Dave, I might just be the youngest viewer of your channel at 14 yrs. plz correct if I'm wrong!:) keep em coming!
i am watching him since i'm13
So what works better, thermal paste or the tape(as seen in this product)?
+Mystickneon thermal paste always winns...but these silicone (presumably) are much easier to handle and also they could be handeled via a pick&place machine....
Way above my budget for toys. You're going to have to give the old one away now. ;o)
do you work with industrial electronics? love your vids, have helped me alot
USB/Serial problem? Probably got an FTDI hidden somewhere in it ;)
I want a set of those test leads!! Any chance of the part number?
BK Precision part number TLPWR1. For $110 you can buy them!
So they just use labview to make this application, and generate exe from that. It should be able to make it on visual basic, i mean, one person could do that in few weeks. I guess they don't have chart painting add-on like SciChart
you should do a teardown on a Programmable AC Power Source model 9805
650MB takes only in Australia 1h to download!!
Ahahaha Dave is like the school teacher that takes 5 points off for the floppy wires on the exam !
Do you actually have Excel installed? If so, you'd probably want to have Excel running for the "Export to Excel" to work. I'm just guessing though.
+Lagittaja +EEVblog ya look to me its looking for microsofts Excel may not work with openoffice Excel
0:00 the 8601 looks older than the 8500
29:01 The problem was the baud rate, i was screaming at my screen. (SPOT THE BAUD RATE!!!!!!!!!!!!!)
I do love your videos but it is painful watching you operate software.
Bummer, no Mac love on the software side.
(not that I really expected that)
that's a very versatile device.
Nice !!
Thanks for the VID's.....
Cheers
Doesn't RTFM and it doesn't work: Great Video Dave!
BK Precision Programmable AC Power Source model 9805 this thing rocks
interesting design. redesign.
The STM32 is a good choice, the advance timers would probably be used for doing precision timing calculation, rise, fall, ect..
They went from a Sigma Delta ADC Sigma Delta AD7708 to a SAR ADC AD7682, for speed. The older AD7708 is very slow.
The software still sucks, for that price they should fix it or redesign it, they use labView components and just drag and drop those components on the window.They should follow keysight they used WPF.
Hmm, SCPI is a very simple human readable protocol over a serial cable in this case. I wonder why even bother with 600mb of visa? Why can't the app just do what it needs to do by just opening a serial port?
Software written in LabView :P
Why can't it export to Excel!?!?! Proceeds to open up libreoffice, i'm assuming you don't have Excel installed...
FYI, those control programs are just all Labview based, so if you have issue with some of the UI it might be because of that. Not to say they made the programs well just that they only used Labview which isn't the most flexible thing in the world.
+natan keddem I expected it to export to a standard .CSV file, or an Excel file which any spreadsheet program can load. Why should excel have to be installed to do this?
+EEVblog That right click menu you got was a built in function in Labview, for that "chart" display ui element. They should have probably created some additional displayed ui control elements for exporting that data in more varied and easier ways. They can't change that right click menu easily since it is a hard coded into Labview
Like I said they could have probably made a better program but they made something quick. Anyone with a half decent grasp of Labview probably made that thing in under 2 days. They needed something quick and dirty, you are looking for well done and polished.
15:25 - The resistors look werid.... O_O
You actually need to have Microsoft Excel installed for the export function to work... It doesn't have a proper built in generator for excel files... Basically hands off the data to excel.exe to create the file... At least thats how the old one used to work.
(saw you have LibreOffice installed, won't cut the mustard for this, but you shouldn't need excel to export ffs...)
It seems the first link is dead ... ( DIY Electronic Load: www.youtube.com/watch?v=8xX2SV...)
That's wacky they disable the USB connection unless you specifically turn it on. It can't be a security feature since there's no password protection on communications. Maybe they don't know how to detect a circuit's been completed. Or maybe they heard network equipment does the same thing and they didn't know it's a security feature. Also, lol at the 650 megabyte USB drivers. I thought HP has massive drivers for their printers but this is a new one. Dell combo packs that contain drivers for all possible hardware for each computer model barely breaks that.
On the export to Excel thing, since it doesn't export to a spreadsheet format it probably uses an Excel plugin to export it because they're incompetent and think Excel is the only spreadsheet program in the world. It probably just gives you the same information as the tab separated text too.
+Noah LeFoot Yes, I thought it was wacky too, I can't see a valid reason to do it.
And yes, lazy programming for the Excel thing.
+EEVblog Perhaps internally there a single serial input and the menu selection switches that serial connection between the three inputs from the back panel.
why still those displays... they consume in time then they are custom made in 5 years you cannot find them annymore... why not putting a nice color dysplay like a 4 inch or 2 4 inch displays...
USB to serial adapters can be a huge pain. They'll work with one device and fail with another for no good reason.
Nice video thank you
What's up with your slogan "Don't turn it on, take it apart" Dave? You should always turn it on first, take it apart, and then turn it on again. This way you know if it actually worked before you started screwing with it.
I think there is only one GPIB controller chip manufacturer left these days ...
Btw, nice review.
The software industry has not moved on from the 1960s. Just imagine if everytime you wanted to design some equipment and you had to design an op amp from scratch and implement it in discrete components. I have this argument with developers at work. Every couple of years they produce the same applications over and over doing everything from scratch. Drives me nuts when good hardware is always let down by a massive software fail.
Dave, does it make tea lol ;-D
Must be nice to have all this stuff given to you. I am a disabled EE currently trying to survive and learn more and can't even get used things donated or discounted to me.
> _Paste into Excel.._
> Uses LibreOffice Calc
Props for showing stuff working on open-source software, but calling it *Excel* just because it's a spreadsheet program? That's just like if I was looking at a copy of Fedora and assuming it was Debian because it's Linux.
+bluephreakr He did refer to it as "spreadsheet" 10 seconds earlier...
I wish you could have bought a clone on eBay and compared. (Note I haven't watched the video yet)
yeeesss
But it's 50w less capacity than the old one.
+Kenneth Scharf I'll take the extra features any day of the week.
On these "wimpy little to220" transistors I can dissipate 200W.
Its the power of sup57n20 soldered to IHS of CPU directly by thermal pad.
Nothing like that IRFP250N rubbish xD
+Arek R.
TO-220 doesn't have
1) The die size capable of handling "continuous currents" as the silicon channel is too small and will end up burning/melting, also the metal tab of a TO-220 is thin
2) The IRFP260/250 is cheap, its got huge thermal mass compared to a a TO-220 and most important the RDS parameter is the main point here... what TO-220 has a RDS on of ~0.08ohms at +/-200watts max with good thermal mass? Note here the mosfet is used in the ohmic region NOT saturation (as a switch as most people use them as).
The 0.05ohm power resistors will help force current share between the fets,this is to help with the varying mosfet(s) rds(on) resistance with temperature, fixed 0.05 + 0.08 ohm + rds(on) will help force current share, each fet can withstand 190w, however its assumed it is used in its saturation region (as a pulse switch), so SOA data will be at the given, however in this case its used in its ohmic region so the SOA for each is NOT 190watt each and calculated based on the instruments V/I parameters... so a 150watt e-load instrument with 4 fets will be 150/4 = 37.4 max watts per transistor which is the SOA (in the linear/ohmic region) so a 200W wimpy mosfet will fail as no SOA parameters has been addressed.
Nope, I know these things, I made few years ago 1,3kW dummy load, 10 in parallel, 0R13 resistors for equal current.
I choosed these sup57n20 in to220 because they had good SOA for DC.
That mosfet have rdson of 33mR at 10Vgs.
But anyway in our use that resistance is not important, because in most cases it will be working as variable resistor.
200W at 15V is in SOA, they dont burn, with 0r13 resistor it can handle 250W
+Arek R its hard to justify your statement, power delivery is proportional to temperature as well (25 *c is not the temperature a e-load works at its 3 or 4 times higher 75 or 80 depending on the heat-sinking used. ) , 250w a single mosfet? no this may work but it will die in the long run, their is a reason why 10 mosfets are used for 250 watts, each only dissipates 25watts under full load (this is SOA + 10% marginal worse case safety). a 1.3k design will die with only 10 as each will use 1.3/10 = 130watts each. there is a BIG different between pulse switching loads 130watts AND continuous 130watts..
Your design is not reliable for the claimed sink figure of 1.3Kw for prolong periods.
By the way, I am designing one too but im busy with the firmware, look at my channel for a preview.I have knowledge with mosfets working with switch mode power supplies in its switching region, but this is a linear mode design, the power parameters are way different.
+Yaghiyah Brenner look at www(dot)nxp(dot)com/documents/application_note/AN11158.pdf
My dummy load was working about 3 years w/o any problems but then was killed by 300VAC spikes from damaged smps.
Another guy have same DL and it works about 6 years.
I now going to build new DL, with digital control, something like these from bk precision.
sigrok FTW!
Those are some lumpy resistors!
+Alyx BioHaz The best kind.
+EEVblog I judge all my test equipment by the lumpyness of the load sharing resistors
@@OneBiOzZ can you please explain what these resistors do and how do they work to share the load please, link to any articles please
Classic Dave... Rages about not working software because he didn't read the manual. I bet everything was explained in the manual. It is okay to read manuals... Usually with Dave the problems start with user not reading the documentation and then the frustration makes it worse. Oh well we kinda expect that from you. ;) Nice video anyways :)
+Hene193 The thing is, what he expects is quite reasonable:
- why would you have to turn interfaces on?
- why are other tabs grayed out when you're recording?
- why it needs excel installed instead of just saving as xls?
And so on...
***** It's matter of perspective. Maybe there is a reason why only one interface can be turned on at the time. RS232 is widely used in printers and industrial systems. That is most likely why it's the default.
But for other things you are right. That other tabs grayed out is just stupid and favouring excel makes kinda sense since this is designed to be used in industry and usually companies run Office. But I don't think that is an excuse for bad design.
+RicoElectrico
- Its not that uncommon to multiplex some outputs (at least in industrial equipment), especially when they both represent serial output which you are unlikely to use at the same time. That way you might get away with a smaller processor with less IO or you can at least skip the constant polling part. According to the picture he put in in post, the chip seems to have a native USB interface though.. which means they would need to do the RS232 by a separate chip. Makes me wonder if they bothered with the processor's USB stack or if they used an external one they were familiar with.
- weird design choice of the software indeed..
- probably because they used the/an excel API because they didn't want to be subject to the whims of the latest file format changes of Microsoft. Since he doesn't have MS excel installed, the API doesn't load. In the end the clipboard export does the same. Not pretty but depending how "serious" the software is I can understand it. The software seems rather simplistic and more there to provide basic functionality, so by my guess they probably weren't throwing hardcore software developers at the project and relied heavily on what was easily doable within their tool chain.
+RicoElectrico it shouldn't require Excel being installed to export to CSV file, like seriously
+RicoElectrico He used excel, it doesn't require it, the data is in a tablular form, kinda akin to a CSV, except this is a TSV, which is perfectly fine.
As for why the buttons are greyed out, probably something for saftey or something, really this isn't a big deal for most people since they wont have their computer so far away when testing, how he even got it that far over USB I don't even know, thats longer than USB cables should be run
perfect
hi i want to learn a can bus
Going in the corner with those cables and making strange sounds is a little to strange for me LOL
Those cables tho eh ?
I suspect you can't export to Excel because you don't have Excel.
* Complains can't export to Excel
* Opens Libre Calc.
I guess if you don't have Excel installed, it won't let you?
Good bit of kit though!
+James Hyde it exports raw data, CSV would be just fine, no need for Excel native file format, it's just laziness, like everything else about the software
the UX is horrible, seriously
Jesus, why those guys don't use Wi-Fi, Bluetooth or something that makes sense for this decade. I understand the legacy. A decent lab requires a lot of money, but at least some videos or resumed instructions. Is that difficult to switch automatically to the proper USB setup? At least blinking something on instrument screen. like: hey, would you like to setup your USB link?
+Thiago Coura Wireless just isn't needed in a lab environment, and sometimes you don't want your test gear to be RF sources. The problem is Dave (like many people) didn't read the manual. It makes sense that you have to tell the instrument which interface to use. A blinking "would you like to set up your USB" would be very annoying if you weren't planning on using USB.
+Chris W I agree with your point about the RF interference. I didn't thought about that, but I disagree that if you deliberate connect a USB cable from the instrument to computer a message or blinking light is something annoying. It's a temporary message to guide you. My point regarding the user experience is not to prohibit you to make thinks in a different way, but if you do, provide the hints to guide the user
this device is just slowing you down... send it to me...
You can't export to Excel, because you apparently don't have Excel on your computer. Jeez.
U don't have to buy HiFly stuff anymore dont u Dave:)
That software is CLASSIC shitty labview.