Re: Strange issue with SSR
Swap a few leads or lines of code to switch SSR and retest.
Do you have the same heaters on all channels? It doesn't appear the SSR has internal protection but channel 1 may be cycling if overcurrenting. You could try swapping heaters around also.
Re: Strange issue with SSR
just put led in series with ssr + and no resister
Re: Strange issue with SSR
Thanks for the suggestions. I ended up swapping the SSR for another and the unit is working as it should.
All loads for channels 1 -3 are the same (100w), with channel 4 being 150w, so not excessive for the relay, they all run cold.
Re: Strange issue with SSR
Scampy, these solid state switch come already equipped with a current limiting resistor already integrated inside the switch.
If you place a led with its resistor in parrallel to the ssr there is the possibility that the current circulating in the ssr branch is not enough to trigger the switch. (Mind these switches work from 5 Vdc to 32 Vdc) since you are using 5 volts (from the arduino output pin), you are in the low current region, so anything that drop a little more the current to the ssr will have the effect to un-trigger your switch.
Follow the amgen advice, connect the arduino pin to your led (+terminal) and the led (-teminal) to the ssr (+terminal) while ssr (-teminal) to ground.
Alberto
Re: Strange issue with SSR
I doubt it is genuine OMRON....