Quote Originally Posted by EddyCurrent View Post
I'm thinking this is going to be my Charge Pump relay circuit. My BOB ENA signal is active low so the relay will be in the 'healthy' state when de-energised, this is not fail safe and I could have inverted the signal but it's going to do. The BOB is supplied by 24vdc and so GND is common to the 5v and the 24V.

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You have C and E swapped over. Its an NPN so E is always to -ve rail.

with only 3 or 4 more components you could make it failsafe and i would...