Raspberry pi help

Products
#1

I bought a raspberry pi and the below

Digital I/O Carrier Board for Raspberry Pi

  • 8-position I/O mounting rack
  • 4 I/O modules (1 DC in, 1 DC out, 1 AC in, 1 AC out)
  • Mounting accessories and ribbon

I wrote custom code to trigger a dc output in python. The relay modules led provided part of the kit illuminate when I trigger via my code. So my code is correct i seem to be toggling the input to the relat moduke[coil].my issue is thats about all that happens ,at the green terminal block i dont have a change in state. Am I missing something any guidance would be appreciated

I know code is correct and I have gpio set at output and I toggle the output pin 0 and 1

#2

Hi Sk7499,

What are you trying to turn on? Are you providing a voltage at the output of the I/O module for it to switch? When you say you “don’t have a state change”, what are you using to check the state with?

Thanks,

Dan

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#3

@Dan_Opto is on the right path here.
You might like to check out our SSR (Solid State Relay) document. It has a lot of good information, specifically about the AC output modules you have (they are similar to our MP series).


The last few pages have some good trouble shooting tips… like how to test them…
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#4

I wanted to check it with a multimeter to see if it changes states then If that worked I was going to provide a load.am I missing something. Usually I verify my code is good by connecting a multimeter to output contact and trigger it via code and if relay changes states i know code and output is good.

#5

As mentioned in the SSR Data sheet, SSR output electronics use active electronic parts, not dry contacts like mechanical relays.
A multimeter can not activate those SSR outputs, it is using the wrong type of signal and so the relay won’t turn on or off.
The key as you have found is the LED indicator on the module, since it is turning on and off as per your code, you are good to go.
Connect up the actual load that the module is going to switch, DC for the DC modules and AC for the AC modules (again, because of the parts in the SSR, you can NOT switch say an AC load with the DC modules) and start doing work.

SSRs are very (very) reliable, most have a lifetime warranty. If the LED is working, the module is working.

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