Where are you measuring that voltage? Does you meter read correctly if you check your power source, the mains supply?
Hi there, I can confirm that the meter is fine, it reads the full 240 volt (a few more but I guess that is expected) from the mains. The bulb is good and tested with a straight mains connection.
I am testing across the high voltage capable SSR output connectors (which say 24-380VAC next to them), not the lower voltage input control connectors of course (which say 3-32VDC next to them). Unless the label on the SSR is incorrect, it is a cheapie, but I would hope that would not be the issue, and I definitely don't want to run 240V AC through the other connectors!
Do I need a resistor on the control side? Apologies if that seems like a silly question, I assumed not since an SSR (according to what I have read) should be a lot easier to drive than a mechanical relay, where I've read it can blow the Arduino if not set up correctly.
Thanks for the reply :-)