The JD-VCC pin on a relay board is used to supply an isolated voltage source to the relay coil. In a typical 5V relay module, you will see pins for VCC, GND, IN (input), and sometimes JD-VCC. The purpose of having JD-VCC is to allow you to isolate the relay's coil voltage (JD-VCC) from the control circuit voltage (VCC). VCC is used to power the control circuitry on the board, which might include things like optoisolators, LEDs, and logic ICs. JD-VCC is used to power the relay coil itself. This is typically the same voltage level as VCC, although it can be different in some configurations. GND is the common ground for both the control circuit and the coil circuit. In many relay boards, there's a jumper that allows you to either isolate JD-VCC or tie it together with VCC. If you isolate them, you can power the relay coil independently, which provides electrical isolation between the control circuit (microcontroller, for example) and the circuit being switched by the relay. The idea behind this isolation is to protect the sensitive microcontroller and its pins from potential back-EMF generated by the relay coil or from any kind of electrical noise or spikes that could be present on the power line being switched.
This NC to NO diagram makes sooooooooo much sense! I've used NC and NO connections for years and never truly understood how it worked. Thank you so much for this video! We need another video from you brother. You put out GREAT content, and I'm needing my Playful Tech fix. Feed us! Much Love!
Thanks - 8:55 solved my problem - switching on and off a 5v set of fairy lights - connecting the switch of the D1 mini to + and ground to ground - powered by a 5v usb connector - spent the whole evening looking for a solution you mentioned in passing !!
i was thinking ... what can be so exited about relays, that you're about to talk for ~23 min?! and i'm impressed! liked the explanation of the NC NO & C, as well as the optocouplers / optoisolators explanation :D very informative. Thanks a lot!
I found your videos when I was looking up how to connect a rotary dial phone to and Arduino, and I must say, I really enjoy them! Your explanations are really thorough, and you don't rush through any details. Keep up the good work :D
Wow, this was great and the best! I just watched a couple of other relay vids, they were ok. But yours, really clarified things at all angles of using a relay. Thanks sir!
Just in case you didn't know, you can also get these same modules in 3.3V configuration. I bought a bunch of 2 relay modules and an 8 relay module all in 3.3V. For Rpi this is critical because they seem to prefer 3.3V over 5V.
Bro! Thank you! I was using a 12v relay for my 12v mag-lock and was pulling my hair out trying figure out why it wasn't working. Lmfao! 5v relay from the nano now works perfectly. Thanks again.
Thanks for the interesting video. I would like to control a solar panel with a 49.5Voc DC rating. I take it these typical Arduino relays won't cut it. Is there anything you could recommend for my project? Tx
My diagram calls for a 12v dual coil DPST relay. I can't find much for dual coil DPST relays, I assume a DPDT will work just as well? Do you have any recommendations?
Hi, I am trying to use the 5V relay for a circuit, but my input signal is coming through a chamber which has digi i/o. How would the input circuit look without an arduino powering it. Do I need to have a 5V power supply in series with the Digi i/o to energize the relay?
A0 to A5 can be used as output pins absolutely fine - just intitialise them as pinMode(Ax, OUTPUT); and then digitalWrite(Ax, HIGH); just as with any other pin.
I use a photoresistor to actuate a relay but i find a problem when the luminosity is not enough to fully turn the relay on , it hesitates for minutes , same for power off at sunset. Do you have a solution ?
Hello! Thanks for all your videos. Your creations are a dream! One question: why do you use relays rather than transistors or mosfets? I often have problems with relays that I have to shake because they get "tired" (mechanically speaking). I'm thinking of changing my strategy...
Mainly for isolation. A relay (combined with an optoisolator) means your load is completely electrically isolated from your control circuit, which is important when you're controlling "noisy" equipment that you want to keep seperated from your delicate microcontrollers!
I have a camper that has 12V switches 40/30 amp relays to open and close awnings etc... Can this help my system and cut back on wiring using din rails? Not too sure if I understand the use?
Great video! I was just wondering, if I was using a 12V relay module (includes its' own protection diode) that can be triggered by 3.3V logic from the microcontroller to control a motorized ball valve (9-24V AC/DC), would I need to include an additional flyback diode across the contacts from the relay to the motorized valve?
Hi Relay experts. I m using an 8 Channel Sainsmart relay board. It requires 12V to activate the relay and it's rated for 30V DC load. I am using it to control 24V items (pin ball flippers). Why after a certain amount of usage does the relay fail. I hear the relay trigger but it fails to complete the 24V circuit after a while. Do I need to place something on the circuit to avoid this damage to the relay. Thanks
is it possible to change the relays from the board and increase the max load without having issues? i have a board with relays rated at 10amps each but want to change the relay to 30/40amps, same voltage, but if i could find same size relay. my board comes with 2 wireless remotes that i like but the relay max load inside is 10amps each, its just not gonna go well when i give it a load of 25 amps from a motor?
You are awesome... i was almost thinking of going to the mental asylum as i was trying a relay on my raspberry pico and i wasn't able to, until i saw your video @12:24 it is so clear and simple. Thanks a lot. Subscribed and liked.
Hello Sir, I plan to use this relay to connect from 5V arduino to 12V DC Pump (4-7A). It is written that the DC adaptor to power the pump is 12V 10A. is it a robust solution to use this relay in a closed enclosure in the farm? or should I upgrade the relay spec? Thank You Very much Sir !
So... you don't need a 12V relay because you have a 12V mag lock. In stead you need a 5V relay because the Arduino gives 5V output? Did I get that right?
That was great thanks. I now understand a lot more than i did before watching this on modular relays, I didn't realise you could control one from a Pi... Interesting. opens up a whole new area..... I do have a question please and would like to know if you can simply control this type of relay by simply sending a low continuous DC voltage say from a new Halo type on/off (not momentary) switch ( the modern LED switches you see everywhere on machines to bread slicers in Lidl etc flat face, normally stainless with a RGB LED halo and "on" icon) They are rated at 3 amps 240 volts or 3 to 6 volts or 12 and 24 volts as well as 240 but not more than 3 amps so basically useless for say a compressor or extractor unit which use higher power. I am building a new C02 laser and would like a nice fancy control panel but I need to be able to switch 220 volts for the compressor and extraction fans and was wondering if I could do it using this type of module or would I need to use a larger fat SSR? :-) I was thinking of getting 5 volt dc versions of these Halo switches and then using 5 v dc positive from a small PSU to simply supply the voltage to light the Halo LED and at the same time use that voltage then as a "switched live" on to the relay via the Halo switch to then use that to switch up to 240 volts AC at 10 amps. Any ideas please on this Thank you. AC no problem but DC it gets complex....
for 4 channel relay , how to calcualte Wattage calculation if I am powering it with Lithium 12v battery ??? is it like 30V x 10 A = 300 Watts for all 4 different relays?? or for just one relay ??
Do you mean power on the load side? (i.e. the device you're turning on?) Or power on the Arduino side (i.e. just the coil which you're powering to switch the relay across?) I don't think either of them will be 300W!
Hi! is a good idea use a relay to activate/deactivate a speaker audio line for control the position of sound out in a room? because in a node-red based sistem the node red dashboard isn't able to controll how html page send a channel audio. With relay all the speaker send all the sound, but node red can eventually deactivate the line of all the speakers and keep on the only playout the sound.
@@PlayfulTechnology thanks, really very useful! node red is lacking in this respect. Yet the audio control should be an important part of both general home automation and for an escape room, but I have seen that there are not many proposals for both commercial and amateur projects. The only more advanced system I've seen is this ua-cam.com/video/SPa9SMyPU58/v-deo.html. Can I recommend making a video on this topic? It would be really great to have a stable and robust system for audio management via MQTT and wifi via node red and esp. It could be done with more locations than Eco dot or google home, but the problem is the dependence on the specific node in node red and above all the fact that if the internet line is interrupted they do not work. thanks for all your videos! (italy)
Huh. You choked on the jd vcc explanation and then figured well I'll mention them separate gnd but didn't connect the dots you yourself drew regarding this & the module you show.
Since these relays are rated for a load of 10 A that means they would not be safe for use with mains power (which has a current normally between 15-20A) correct? What relays would you suggest for use with a microcontroller that can handle mains power?
The point is that a microcontroller CANNOT handle mains power. We need a relay controlled by low voltages and currents from the microcontroller to switch the higher voltages and currents of mains power.
This is an old video, and addressed the issues that most of my subscribers were asking at the time. If you let me known what it is *you* want to know about relays, I'll happily update it ;)
The JD-VCC pin on a relay board is used to supply an isolated voltage source to the relay coil. In a typical 5V relay module, you will see pins for VCC, GND, IN (input), and sometimes JD-VCC. The purpose of having JD-VCC is to allow you to isolate the relay's coil voltage (JD-VCC) from the control circuit voltage (VCC).
VCC is used to power the control circuitry on the board, which might include things like optoisolators, LEDs, and logic ICs.
JD-VCC is used to power the relay coil itself. This is typically the same voltage level as VCC, although it can be different in some configurations.
GND is the common ground for both the control circuit and the coil circuit.
In many relay boards, there's a jumper that allows you to either isolate JD-VCC or tie it together with VCC. If you isolate them, you can power the relay coil independently, which provides electrical isolation between the control circuit (microcontroller, for example) and the circuit being switched by the relay.
The idea behind this isolation is to protect the sensitive microcontroller and its pins from potential back-EMF generated by the relay coil or from any kind of electrical noise or spikes that could be present on the power line being switched.
This NC to NO diagram makes sooooooooo much sense! I've used NC and NO connections for years and never truly understood how it worked. Thank you so much for this video! We need another video from you brother. You put out GREAT content, and I'm needing my Playful Tech fix. Feed us! Much Love!
Why didn't you just look at the diagram on the relays or google them?
Thanks - 8:55 solved my problem - switching on and off a 5v set of fairy lights - connecting the switch of the D1 mini to + and ground to ground - powered by a 5v usb connector - spent the whole evening looking for a solution you mentioned in passing !!
i was thinking ...
what can be so exited about relays, that you're about to talk for ~23 min?!
and i'm impressed!
liked the explanation of the NC NO & C, as well as the optocouplers / optoisolators explanation :D
very informative. Thanks a lot!
Again another excellent explanation. Thank you for explaining the K1/K2 diagram. I have seen this many times and didn't know exactly what it meant.
I found your videos when I was looking up how to connect a rotary dial phone to and Arduino, and I must say, I really enjoy them! Your explanations are really thorough, and you don't rush through any details. Keep up the good work :D
Wow, this was great and the best! I just watched a couple of other relay vids, they were ok. But yours, really clarified things at all angles of using a relay. Thanks sir!
Just in case you didn't know, you can also get these same modules in 3.3V configuration. I bought a bunch of 2 relay modules and an 8 relay module all in 3.3V. For Rpi this is critical because they seem to prefer 3.3V over 5V.
Unless I'm mistaken, most 5v rated relays can also trigger at 3.3V.
Some 5v relays can operate just fine on 3.3v, no need for 5v at all
Thanks for the information about active high and active low roles.
Thank you for such clear explanation
Thank you!! This is so helpful. I appreciate your clear and concise presentation.
20:58 explica cómo usar el aislamiento entre el circuito lógico de control y la etapa de potencia del relé
Great video. I needed this info for my next project. I was about to use a 5v relay where I was using 12 volts. Thanks again for all your videos.
Absolutely beautifully explained. Great video and great diagrams to help nail the points home.
Is it safe to put multiple connection in the common terminals?
Wow! Ive learned alot. Thanks!
Bro! Thank you! I was using a 12v relay for my 12v mag-lock and was pulling my hair out trying figure out why it wasn't working. Lmfao! 5v relay from the nano now works perfectly. Thanks again.
I need to remotely opperate my generator. Can you show a video on how to connect an antenna and fob to opperate the relays A and B?
Thanks for the interesting video. I would like to control a solar panel with a 49.5Voc DC rating. I take it these typical Arduino relays won't cut it. Is there anything you could recommend for my project? Tx
Great video, lot's of info, all well described and shown, great job mate. Keep it up.
nice info. wanted to make a request on how OAC-5H series relay work
Did the mosfet video ever get made? The ticking of the relays is driving my wife bonkers.
uh, that was quite a brilliant explanation！ thanks a lot.
This is such a great explainer video! Thanks
My diagram calls for a 12v dual coil DPST relay. I can't find much for dual coil DPST relays, I assume a DPDT will work just as well? Do you have any recommendations?
looking to use a relay to move a dc motor with 2 push buttons and not a arduino . Do you have a video for that?
is there a difference between jqc3ff and srd 05vdc relay module?
Hi I have a boom gate and a roller shutter gate and want to open both at the same time, however I only have one trigger in order to do it
Hi, I am trying to use the 5V relay for a circuit, but my input signal is coming through a chamber which has digi i/o. How would the input circuit look without an arduino powering it. Do I need to have a 5V power supply in series with the Digi i/o to energize the relay?
But the 6 analog pins (A0 - A5) on the Arduino can only be used as input pins not output. How are you using the A0 pin to turn the relay on or off?
A0 to A5 can be used as output pins absolutely fine - just intitialise them as pinMode(Ax, OUTPUT); and then digitalWrite(Ax, HIGH); just as with any other pin.
How to wire, power and control the 12V Relay module?
I use a photoresistor to actuate a relay but i find a problem when the luminosity is not enough to fully turn the relay on , it hesitates for minutes , same for power off at sunset.
Do you have a solution ?
Hello! Thanks for all your videos. Your creations are a dream!
One question: why do you use relays rather than transistors or mosfets? I often have problems with relays that I have to shake because they get "tired" (mechanically speaking). I'm thinking of changing my strategy...
Mainly for isolation. A relay (combined with an optoisolator) means your load is completely electrically isolated from your control circuit, which is important when you're controlling "noisy" equipment that you want to keep seperated from your delicate microcontrollers!
@@PlayfulTechnology OK, I get it. Thank you for answering 🙏
I have a camper that has 12V switches 40/30 amp relays to open and close awnings etc... Can this help my system and cut back on wiring using din rails? Not too sure if I understand the use?
Great video! I was just wondering, if I was using a 12V relay module (includes its' own protection diode) that can be triggered by 3.3V logic from the microcontroller to control a motorized ball valve (9-24V AC/DC), would I need to include an additional flyback diode across the contacts from the relay to the motorized valve?
Can I use the same battery for both outputs on the relay for 2 different circuits? I did this but the relay keeps clicking. It can't stay on.
can you help make to 3v relay?
The picture of the relay am asking about is the smallest relay black in colour then it has fin legs only four fins leg.
Hi Relay experts. I m using an 8 Channel Sainsmart relay board. It requires 12V to activate the relay and it's rated for 30V DC load. I am using it to control 24V items (pin ball flippers). Why after a certain amount of usage does the relay fail. I hear the relay trigger but it fails to complete the 24V circuit after a while. Do I need to place something on the circuit to avoid this damage to the relay.
Thanks
I connected a sk3f-s-5vdc-c relay with esp32. But it doesn't work. Is there any way to fix it?(without changing the relay module)
can i use transistor instead?
is it possible to change the relays from the board and increase the max load without having issues? i have a board with relays rated at 10amps each but want to change the relay to 30/40amps, same voltage, but if i could find same size relay. my board comes with 2 wireless remotes that i like but the relay max load inside is 10amps each, its just not gonna go well when i give it a load of 25 amps from a motor?
You are awesome... i was almost thinking of going to the mental asylum as i was trying a relay on my raspberry pico and i wasn't able to, until i saw your video @12:24 it is so clear and simple. Thanks a lot. Subscribed and liked.
Hello Sir, I plan to use this relay to connect from 5V arduino to 12V DC Pump (4-7A). It is written that the DC adaptor to power the pump is 12V 10A. is it a robust solution to use this relay in a closed enclosure in the farm? or should I upgrade the relay spec? Thank You Very much Sir !
Is possible to use this relay for 42dcv?
No - the SRD-05VDC-SL-C which is the common model I show here is only rated up to 28VDC.
So... you don't need a 12V relay because you have a 12V mag lock. In stead you need a 5V relay because the Arduino gives 5V output? Did I get that right?
remconet Yes, exactly!
Wow, I AM starting to get it! Thanks so much.
Can I use this relay to control a 12V connection on the output side?
3:20
That was great thanks. I now understand a lot more than i did before watching this on modular relays, I didn't realise you could control one from a Pi... Interesting. opens up a whole new area.....
I do have a question please and would like to know if you can simply control this type of relay by simply sending a low continuous DC voltage say from a new Halo type on/off (not momentary) switch ( the modern LED switches you see everywhere on machines to bread slicers in Lidl etc flat face, normally stainless with a RGB LED halo and "on" icon)
They are rated at 3 amps 240 volts or 3 to 6 volts or 12 and 24 volts as well as 240 but not more than 3 amps so basically useless for say a compressor or extractor unit which use higher power. I am building a new C02 laser and would like a nice fancy control panel but I need to be able to switch 220 volts for the compressor and extraction fans and was wondering if I could do it using this type of module or would I need to use a larger fat SSR? :-)
I was thinking of getting 5 volt dc versions of these Halo switches and then using 5 v dc positive from a small PSU to simply supply the voltage to light the Halo LED and at the same time use that voltage then as a "switched live" on to the relay via the Halo switch to then use that to switch up to 240 volts AC at 10 amps. Any ideas please on this Thank you. AC no problem but DC it gets complex....
Great explanation, thanks!
Super Video, thank you so much!
for 4 channel relay , how to calcualte Wattage calculation if I am powering it with Lithium 12v battery ??? is it like 30V x 10 A = 300 Watts for all 4 different relays?? or for just one relay ??
Do you mean power on the load side? (i.e. the device you're turning on?) Or power on the Arduino side (i.e. just the coil which you're powering to switch the relay across?) I don't think either of them will be 300W!
Hi! is a good idea use a relay to activate/deactivate a speaker audio line for control the position of sound out in a room? because in a node-red based sistem the node red dashboard isn't able to controll how html page send a channel audio. With relay all the speaker send all the sound, but node red can eventually deactivate the line of all the speakers and keep on the only playout the sound.
Yes, I've used multi-channel relays to divert sound to speakers in different areas. It's simple and works well!
@@PlayfulTechnology thanks, really very useful! node red is lacking in this respect. Yet the audio control should be an important part of both general home automation and for an escape room, but I have seen that there are not many proposals for both commercial and amateur projects. The only more advanced system I've seen is this ua-cam.com/video/SPa9SMyPU58/v-deo.html. Can I recommend making a video on this topic? It would be really great to have a stable and robust system for audio management via MQTT and wifi via node red and esp. It could be done with more locations than Eco dot or google home, but the problem is the dependence on the specific node in node red and above all the fact that if the internet line is interrupted they do not work. thanks for all your videos! (italy)
My arm is aching just by watching him hold that relay for that long without any support.
Huh. You choked on the jd vcc explanation and then figured well I'll mention them separate gnd but didn't connect the dots you yourself drew regarding this & the module you show.
Since these relays are rated for a load of 10 A that means they would not be safe for use with mains power (which has a current normally between 15-20A) correct? What relays would you suggest for use with a microcontroller that can handle mains power?
The point is that a microcontroller CANNOT handle mains power. We need a relay controlled by low voltages and currents from the microcontroller to switch the higher voltages and currents of mains power.
@@johncherry108so can I use this relay to switch on and off a high powered LED from uk mains ?
veri nice, thanks!
"Everything you need to know about RELAYS" Everything? You really didn't even scratch the surface.
This is an old video, and addressed the issues that most of my subscribers were asking at the time. If you let me known what it is *you* want to know about relays, I'll happily update it ;)
Hi
"playful" - call it lazy ;) for 75% you sit still, poke your hand into cam once in a while and mumble things... this is very low content quality!