I have set up a test rig to test out Temperature controllers. An SSR is activated to switch on a 240V LED when the T/C is calling for Heat. Trouble is that even when the SSR is not switched on there is a leakage current across it that lights the LED anyway. I spoke to the SSR manufacturer (Crydom) who said "yes there will be leakage across due to the internal snubber, enough to light a 10mA LED". They suggested either to use a snubberless SSR or put a power resistor in parrallel with the LED to null the leakage current. I cant remember my maths and what ever resistance I use across the LED, it only dims it very slightly. Any advice on solving this problem, formulae / resistor size / or any other advice greatfully recieved.
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