MK 125 Help - Relay Doesn't switch!


Could anyone help, I have put together the light sensitive switch and the LED lights up whenever light isn’t present. Problem is that the relay doesn’t switch, on one end there is always continuity but on the other never any contact. I’ve checked for shorts and dry joints but am a little confused. Did anyone experience the same problem ? Any Idea what it can be ? Your help would be much appreciated.



Check your power supply, make sure you get 12VDC at the input. Desolder the relay and apply 12VDC to the coil, to make sure it works fine. Check your assembly. Make sure R2 has the right value. Check all PCB tracks which connect to the relay.