It’s a relay race! 😉

As someone who never worked with externally powered relays and now needs to control 80 relays at once this was incredibly helpful!

I’ve never tried using relays but I’m gonna buy a board now. Thank you for actually showing the correct way to use them. I was wondering how to the whole video.

You deserve my respect. Love from Goa

My experience is that those relay boards have a large area of copper plane common to grounds for both the input logic and the relay coils. With separate VCC/VJD supplies for multiple relay modules there will probably be a ground loop via the Arduino logic ground wires. Those will then be carrying an unwanted share of the relays' coil current. Where that extra current is carried on the Arduino pins/tracks depends on the positioning of the signal ground wires. It wouldn't have been a big design difference to have isolated the two grounds on the board with another jumper. Tried the obvious simple copper cut to no avail. There appears to be an hidden interconnection as well - possibly a via.

wow that is impressive, i didnt know a arduino was that powerful, well i am not thinking its just a toy now. Now i am thinking you could hook up twice as many led's with resistors with the normally open and closed, it would be a hell of a light show

This was fascinating!

Thanks for making this video:)

using the i2c bus and pcf8574 module and 8 ch relay board, you could get a lot more as I measured 13.2ma on the 5v line with all 8 channels driven (relay's driven with JD-vcc connected to ext 5v supply of course.)

many many thanks, this has been very INSPIRATIONAL+informative, one question, i have 1 motor and i want to use 2 battery packs, one as a backup, then my question: how many channel will i need ??? and again many many thanks for your inspirational informative presentation

sir can i ask a question, i am using three 16 channel relay 12V to my arduino mega, what is the pin connection from arduino to relay and can i use 12v charger to directly connect it to the power source of the relay?

Good explainations

thanks for this experiment sir its very helpful

Lovely :) With some added shift registers, only sky (and CPU speed) is the limit ;)

Impressive video and impressive stockpile of relays! A few years back, I also had an 'out-of-hand' project where the Client wanted to control hundreds of relays with a single Arduino. He also wanted to control them remotely via PC touchscreen up to 200 ft away. Yikes! The PC screen control wasn't a problem as I'd been interfacing Arduino and VB6 for years. The signal distance also wasn't a problem as I use HC12 long range transceivers in many projects. I didn't want to use multiplexer boards as I wanted much simpler program control. While also playing with a neopixel string project and it hit me... One can control 256 neopixels with one pin of a Nano so why not use the light from neopixels (similar to optocoupler)? Using WS2812B chips and LDRs one can easily control 256 relays with 1 pin of a Nano. By using WS2811 modules (3 outputs each - R, G & B) one can control over 11,000 relays with one Nano :) If interested do a KZfaq search for "nano 256 relays"

Great expirment!! Loved the idea Im new to this but i have a question:the boared is only conected to relay with vcc pin Nd relays are powered by external source how you control relays by desire ?

I've got a small project that I'm working on. I have a computer case that has 3 RGB fans in the front of the case. However the motherboard doesn't support the fans. (other than the fan part) The red and green will light with 5 volts but the blue requires 12. Even 9 volts won't light the blue led. Can these relays work with 12 volts? I've created a prototype using an Arduino Uno and a relay sheild but so far I can't seem to get the relays to trigger. Any thoughts or suggestions will be greatly appreciated.

I think the idea of how many can you connect is great maybe you can do this with other products. Thanks for the video

I`ve connected all the digital pins on a mega up to LED`s for a flashing sign. Worked ok with just the usb connected to the mega.

Awesome bro👍👍👍👍 Also make video on ESP32 AND ESP8266 5v and 3.3v power current limits

thank you! I'm looking for a solution to power up 30 relays, and here I got an answer.

Thanks for this video. Most people do not know how to make proper connection between the relay and controller using the optocoupler.

This is awesome... Hope you can clear something up for me. I am new to this and have an arduino mega, arduino shield and wifi boad. I can control H/O trains with this setup... DCC++EX and it works great. I want to control each track turn out and I understand I need 1 relay per track... say 1 for left and 1 for right. I need 30 relays so 4x8 relay boards are good. I understand I need 30 outputs from the mega to 30 pins of the 4 relays.. all good... Need power and ground per relay board.. all good there.. What I dont know, is you mention needing a 5v from relay board back to a 5v port on the mega and I see that in your example of the 8 relays... but where do you connect the others? how many other 5v spots are on the Mega that you used? That mess, beautiful that it was lol, i couldnt follow traces to see... appreciate any help!

Could you make a whole neural network from relays 😂

AnotherMaker- You should have written a for loop and turn them all on in sequence over the course of a few seconds or so. Would have been cool to hear.

good video.

I've personally ran 32 relays off a mega without issues when I built a replica countdown clock for channel 4s offices. I did end up using external power though you said something about the stability being dependant on the load on the relays but this isn't even remotely a factor, the relays will draw pretty much the same power regardless of load atleast up until the point where the load is over the spec of the relays and the contacts start to weld together

I wonder why you connect the VCC from the relays to the arduino, is it because both outputs of the charger are isolated from each other?

love it

The first sentence describes my projects perfectly xD every of my projects go out of hand xD

Where the jumper is my 4 channel relay board lacks a ground pin. My only ground pin is with the input pins. How do I wire up my arduino and external power supply in this case? And would there be a reason some boards lack the ground pin while others don't?

Please explain...... Need to operate 16 channels . Must on 1 mnt then switch to next channel... Every channel one mnt .. after 16 mnt oll off.. if i want to operate again must start from beginning channel 1 to 16 ... One mnt for every chanel

How many water sensor and switches for little water pump will that 1 Arduino manage?

What was the sound when you used 68 relays?

Can relays be modified so that they operate silently? (for a musical instrument)

Hey i have a question please.. can i connect more then 1 bluetooth relay to Arduino at the same time?

Hi sir I wanted to know something regarding the same I m currently working on a robot, which already has uses about 40 io pins of mega(more extensions to come) - which I'll power directly from the 5v pin of l298n board, which itself is powered up by 2 18650 Li ion batteries. So, 1.) Can I add another l298n, powered by the same 2 batteries, to power up the relays? As I don't wanna add 2 more li-ion batteries, just for 4 relays 2.) In future, I'll add more sensors/modules, that would draw more and more current, but the max recommended current that can be drawn for one IO pin is 40ma(max for the board itself is 200ma) What should I do in that case? Btw, i really liked the concept of ur video 🤝

Can you help me with my project? I use 2 relay to control my DC motor for forward and reverse the motors rotation, but when i control it using my arduino, my arduino program was crash and error, and i had to reset it again so it can run again, i already use an external power supply for my relay 4 channel modul, but it just the same, can you help me with that please

Is it possible to distribute a large load across multiple relays?

Here i am watching video and me with my little humble only 8 relay board😅

Can you suggest me, i wanna make multi time clock 7 segment with 1 arduino

how can a relay project benefit in music production, and how many adding many sequences of relay circuits benefit the same cause? thanks

can we use its Arduino Nano Also ?

Where can I find the electrical wire bu 30 feet long? I need auto plant waterer. I want garden . Disabled, the plants will still get water and not die as fast.

Not sure what the thinking is with connecting vcc from the relay boards to the Arduino 5v, generally you only need to common the ground vss connections to each other. I've done this kind of experimentation and I appreciate this configuration works, perhaps it's because it's active low as opposed to high. Unsure...

Why do the relays need to be isolated from arduino? Are those optoisolator chips on the relay board?

awesome ! now make a tune with them

I found you from simple electronics!

I want to have a realy module that I can easily connect to arduino. I want to control 12V heather, humidifier ect. But can't find any information about the quality of the relays. They all seem to be cheap chinese quality, and I don't want any dangerous situation with them.

can you post the code aswell?

Novice question....how are the control signals connected to each of these relay boards? Do you split the 5v line coming from the arduino to connnect to all the boards in parallel?

Im gonna try not connecting that ground to arduino.. hopefuly it stops arduino from resetting whenever relay is switched..

make video 16 relay 5v

What is the latency of this relay ?

how about signal interference?

I was just wondering if I could connect 50 solenoids to one arduino

me here after breaking my power supply that handles switching of relays

What are you doing tonight? --> I'm going to blow an arduino mega with an ungodly amount of relays. That's what I'm talking about!

I’m in USA. GA. U?

8:56 quem ai se afastou da tela com medo de explodir tudo? rsrsrs

But.... My arduino nano can't even power 16 channel relay..not sure why... And if I use external 5v supply for Relay... It does not trigger the relays... It works only when connected to board power supply... What am I missing here.... Can you share a circuit diagram... For two 16 channel relay with shift register...

Your relays are normay closed they are not taking any power when u wright them low

Hmm who asked those questions name them :-)

We can use 74HC595+Arduino UNO elegantly, and it is not a problem to control hundreds of relays