SDR 12 V Relay LED is on but NO coil activation

Dear all,

I'm trying to build a home automation project using Arduino UNO and SDR 12V 4-Channel relay. My code is working fine because i've tried to use some leds instead of the relay and it was working fine. However, i'm not able to get the anticipated results after integrating the relay.

The relay seems to be powered and the led is on. However, i can't hear the sound click of the coil activation and the load ( a lamp in my case) is not powered.

Here is the configuration I did:
Relay DC+ to 5V Arduino
Relay DC- to GRD Arduino
Relay IN1 to Pin 3 Arduino

Connector side:
Relay NO1 to a load which is connected to 12V power supply positive side
Relay COM1 to 12V power supply negative side.

I'm not sure what's the problem exactly. Any advise, please?
Plus, I'm wondering what does S1, S2, S3, S4 relay jumpers mean??? Do I need to do any configuration with them? or maybe S1?

Your time and help is highly appreciated!

Best regards

I believe the jumpers are to configure each input to energize the relay with "High" or "Low" level (IN1 to IN4).

Its unclear to me what the DC+ and DC- terminals are for. The relay coils are 12V, but the driver circuit also needs power. If the DC+ is for 12V and the DC- is a common ground, then the opto isolators become redundant. Do you have a schematic for this board?

12volt relay coils need 12volt to activate. 5volt (DC+) from the Arduino is not going to cut it.

Arduino's 5volt supply hasn't got the capability to power four relays anyway.

If you power the Uno with a regulated 12volt supply on the DC jack, you can use a wire from Vin to DC+ to power the coils.

Not sure how they have managed low or high active switching.
Educated guess: leave the jumpers on "high". A "high" on the Arduino pin should now activate the relay.
There won't be (can't be) opto isolation with this board, because primary and secondary grounds are shared.
Leo..

Wawa is right, 12V + to DC+, 12V - and Arduino GND to DC -, Arduino output pin to IN1, 2. 3 and 4, jumpers on HIGH.

post a link for the relay.
Most of those 5V relay modules are ACTIVE LOW. Relay is energized with a LOW, not a HIGH on the input control pin (ie: IN1).

Also, there is usually a jumper that allows you to power the relay from an external source (like 12V).

As Wawa pointed out , it is a 12V relay, but on reading your post you clearly already knew that since you posted this:

I'm trying to build a home automation project using Arduino UNO and SDR 12V 4-Channel relay

Why then, would you post this:

Here is the configuration I did:
Relay DC+ to 5V Arduino


Does that make any sense ?

@raschemmel.
Did you see the attached image (post#1). It's not the usual relay card.
I traced the "LOW" selector pins to the +12rail.
If you connect the jumper to "LOW", you might never be able to turn the realys off with Arduino's 5volt logic.
Leo..

@raschemmel.
Did you see the attached image (post#1). It's not the usual relay card.
I traced the "LOW" selector pins to the +12rail.
If you connect the jumper to "LOW", you might never be able to turn the realys off with Arduino's 5volt logic.

Didn't we discuss this in a different post where we concluded that if the Opto isolator input led uses the arduino Vcc (5V), then a Low on the IN1 grounds the led , completes the circuit and turns on the opto output which uses a different Vcc.

Am I confused ?

This (image from post#0) is a different relay board.
It does NOT have a JD-VCC jumper.
It has four "logic high" or "logic low" jumpers.
Maybe I'm getting confused too. So many questions/posts about different relay boards lately.
Why can't there be only one system that every noob understands.
Leo..

Why can't there be only one system that every noob understands.

They still wouldn't understand. That's why they're called "Noobs".

Besides, if they did, we'd be out of a job.... ;D