leakage current in SSRs always trips people up. I was measuring voltage at the output of my SSR, with no load attached to it, and was getting like 80V or something before I realized what was going on.
I also have an indicator light that REALLY behaves oddly. The light is a 240V neon one. One side of the light is fed from an un-switched 120V hot line. The other side is fed from the output of my SSR.
But... In front of the SSR, there is a contactor that is OFF, so there is no voltage available on one side of the SSR.
Basically, I have this circuit:
[120V line] ----- [neon light] ----- [SSR] ---- [nothing]
The light STILL lights up dimly.
Turns out... There is a capacitor network in the SSR. The cap inside the SSR is charging/discharging as the 120V line swings back and forth. The delay in the capacitor reaction is causing a tiny bit of voltage difference to be seen across the light.
That one REALLY boggled me for a while.
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