Wiring 12v relay wiring

Hey all. Searched google and here and cannot find the exact answer.

My board is a 12v controller 8ch relay board. I connect the dc+ and dc- to a 12v battery and then put the jumper cables to the in1-in8 from digital pins 2-9

I don’t have a vcc so cannot use some of the diagrams I’ve seen. Please see attached photos of my setup

Many thanks

I hope You connect dc- to Arduino GND.
I can't see any attachements. System failue or You forgot to click the button?

Please see attached photos of my setup

Can't see any.

Once we can see what you have then we might be able to help. At the moment all we have to go on is a vague description and telepathy.

Assuming you have not already done so please read 'how to use this forum - please read', there are clues in the title.

Sorry I’m struggling uploading images from my phone. Says photo isn’t correct file type.

Should display the photos in my dropbox

You need to send images that don’t have any metadata (Exif data) attached to them.

Using a relay board and uploading images.... My capacity as medium is still not enough to understand.
Are You possibly using some kind of code?

The relay board inputs need a GND going to the Arduino GND.

We need to see a link (and schematic) to the relay board.

I am using the PS3BT code I have posted in another thread. I have added digitalWrite(2,HIGH) to send 5v down one of the pins which goes to in8 on the relay when I press the up button on my PS3 pad. Down button does 2,LOW to turn off the relay The arduino is doing it correctly but the relay doesn’t switch.

I haven’t put any wiring to the gnd on the arduino uno r3 board nor have I put 5v from the uno board anywhere

The relay board I’m using is this 5V 12V 24V 1-2-4-8 Channel Relay High Low Level Optocoupler Module Arduino PI | eBay

Should display the photos in my dropbox

It does. Clear photos that tell very little.
Please upload a schematic. I suspect from your vague description that you have not connected 0V on the Arduino to the battery -ve.

I haven't put any wiring to the gnd on the arduino uno r3 board

No surprise then that it doesn't work.

“ I haven't put any wiring to the gnd on the arduino uno r3 board nor have I put 5v from the uno board anywhere”

Looks like you have your Arduino 8 digital outputs going to 8 relay input terminals.

You will at need a common ground for these digital signals to return to the Arduino.

So I am to connect the uno gnd to the gnd which is linked to the 12v battery gnd?

So I am to connect the uno gnd to the gnd which is linked to the 12v battery gnd?

Yes.

How else is the circuit going to be completed? They are called circuits because the little electrons get home sick and like to circulate back to their home, in their power supply :slight_smile:

(Please understand I am feeling silly and mean no offence, anyway, you are more likely to remember that way)

No, you need the Arduino GND connected to the ‘relay board input’ GND.

We really need to see the ‘link’ and ‘schematic‘ of that relay board.

There is probably an opto-isolator on the input of each relay channel.

If You dislike the GDN connection between the controller and the relay board You need to use wireless transmission of the relay controlling signals.

So I am to connect the uno gnd to the gnd which is linked to the 12v battery gnd?

Yes.

No, you need the Arduino GND connected to the 'relay board input' GND.

Now you are confused as LarryD is disagreeing with me. Unless I have misunderstood him we are saying the same in different ways. Connect 0V (ground) at the boards, not at the battery terminals. If Larry thinks I've misunderstood him I'm sure he'll be along soon enough to confuse you more :confused:

I’ll grab a photo of my setup asap

Not a photo, but that might help.
Draw it out on paper (a schematic), so you understand what you’re doing, we don’t.

The relay boards in the link have 5 volt coils, not 12 volt.

They are definitely 12v coils.

I’ve added more high quality photos to my Dropbox

I’m doing a paper drawing now