@@AnotherMaker i have an application where there is a relay and a fuse to a 12V load (only 1) I was considering using a relay module and ditching the fuse (is this safe or a relay module does not replace a single oldschool automotive relay + fuse)? I then found out about mosfet modules that are much more compact, now could these be a direct replacement to my old fuse relay combo?
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.
True. My boss a old school electronic technician told me about a place where the whole walls was covered with relays and contactors. The noise in there and the movement was amazing he said. It was something to experience.
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 RU-vid search for "nano 256 relays"
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
@@AnotherMaker You are using the same charger to supply both the Arduino and the relays with power. A charger with two outputs does not normally have separate 5V outputs so there is no separation between the Arduino and the relays
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
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?
Hey, thanks so much for all this information! Two questions: What is loud (you mention that the video does not properly show how loud it is) in the final setup? And how to connect all the VCCs to the Arduino? Is that at the breadboard?
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.)
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
Perhaps he meant the load of each coil. The single relay I'm playing with right now pulls about 70ma to switch. So with one on, no problem, With lots on at the same time, Lets just say a cheap phone charger ain't gonna cut it. Load on the relay terminals is I agree, irrelevant, so long as the relay and the isolation can cope. Each opto only draws a few milliamps, plus the indicator LED. With a 1k resistor in series. So going over the Arduino current limit shouldn't be a risk. Something in the hundreds of ma per group of pins if I remember correctly.
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
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!
Sorry for the slow response. The IDEAL way to do it is to grab the 5v from a second usb charger. That's how I normally do it safely. The mega has at least 4 5v pins and sometimes I take a "normal" IO pin, set it to output and write it high. to make more of them. So even though the board is being "powered" externally, that 5v is still connected to the arduino.
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.
Overall there of pretty decent quality. A RU-vidr named a v e did a counter and showed how many times one of these things could turn off and it was in the hundreds of thousands if not millions.
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 ?
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.
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.
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.
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
I'm sorry. I don't have a whole lot of insight on that sort of thing. The only thing I'd guess is that you're using too much power. You probably want to power the relay separately from the arduino and see if that fixes it.
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?
I wonder if some of the ones that lack optical isolation don't have that other ground pin. Does yours have a 4 pin chip in front of the relays or a 3 pin? 4 pin is the optocoupler. You could probably use the same ground for both.
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 🤝
Thanks! I wish I had better advice for you off the top of my head. It really comes down to measuring or calculating the amount of current used vs the max of the various components (and leaving yourself some room). I don't know all the numbers off the top of my head
that did not work. what worked just so anyone might have the same problem is I connected a 1000uF electrolytic capacitor to the vcc and ground pin of the arduino using 10cm dupont female connectors. and no more reset..
There are little power surges when they operate and you wouldn't want to damage the sensitive electronics on the Arduino. Those are optos.... Although it's not uncommon to find the cheaper relays without them
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.
Know how to program switches with moisture sensor on a switch. And 5volt mini water pump on 2nd switch? If dry -turn on water pump......when it senses water- turn off water pump?
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?
Whew. I couldn't tell you. That would be an interesting experiment though. I used a bunch of these in another video to control a claw machine and it "felt" instant, but I'd guess 100ms.
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...
The opto thing triggered when the led from the arduino is activated, this will triggerred the relay switch, so no common gnd is needed as per usual. howtomechatronics.com/tutorials/arduino/control-high-voltage-devices-arduino-relay-tutorial/
I looked for available code already written but did not find it.... I do not know how to load code in an Arduino... either.. I’m new but née badly to water garden vegetables for me. I am disabled. But can learn by video and automate it. I have friend to run water lines for me once I build it and solder it all together. I will need to power each 8 switch brick and Arduino. I will offer pay for your assistance to guide me. Wanna help some?
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...
Each style of relay has a different ability to output power. That's why I used the mega on this one. I don't tend to use shift registers. I can tell you the easier/better way to do it is to actually do the VCC/Ground on the relays from an external power source and then only use the arduino to drive the pins.
@@AnotherMaker yeah.. I'm using external source to power relays and connected the outputs to relays pins.. But it dosnt work... Or trigger... I think ground of relays and arduino should be joined together
