Hello everyone,
I recently bought a relay module to control the power supply of a lamp. I was testing it first with a LED, but I can't get it working. After looking everywhere, I think that my circuit is correct.
I'm clueless, and I'd appreciate some help.
Basically I have an sketch that sets the digital pin 8 to HIGH. The 5V of the Due is connected to VCC, Ground to GND, and the pin 8 to IN1 of the relay. I tried IN2, and the results are the same –nothing. At the other side of the relay I have the LED connected.
If I set the connections on the NC part of the relay everything works fine, but what I'm trying to do is set it to the NO part, and open it only when the pin 8 of the Arduino is HIGH.
There goes a picture, in case I'm missing something on the explanation.
NO will close the circuit (turn on the LED) when Arduino pin is high.
In any case, the relay seems to work on at least on side, so the wiring up to the relay is ok. The relay clicks, right?
Upload the blink sketch and use a multimeter set on continuity test (buzzer) to see if the connection is being closed and broken on clicking.
You are using the common pole on the relay for one of the wires, right?
When you tried IN2, you hooked everything to the other relay, right?
Man, that's weird. I followed your instructions, but it worked just uploading the blink sketch. I had two errors on the circuit. First, the IN1 corresponds to the other relay. Shame on me. Second, I must have misunderstood the little drawing on the board. Apparently, the "closed" circuit drawing corresponds to the NO, since setting the pin HIGH turned on the LED.
That is, obviously, a combination I hadn't tried, since setting the pin HIGH on the NC was opening the circuit, making me wonder why didn't it work...
Your LED test may have failed due to the Due having many pins that can only source 3 ma and sink 6 ma. Other pins are better at 9 ma source, 6 ma sink. This is significantly different than the AVR series 8 bit parts.
I don't think so. I looked it up on the schema from the thread you specified and according to it the pin 8 is a high-current pin (source 15mA, sink 9mA).
Switching the NC for the NO worked fine.