I have a 12v relay wired like the pic below: pin 30 is a switched 12v feed. 87A goes to my led device that i'm powering. When 85 and 86 are energised using another circuit then it interupts the power to 87A turning it off. But then I have another circuit that if that circuit is live then i don't want the power to the 87A device to be cut even though the coil is energised. if that makes sense? Is there a way I can do this? possibly with the addition of another relay maybe?

 

#30 is what is called Com (Common) 87A is the NC (Normally Closed) contact and 87 is the NO (Normally Open) contact. When the coil 85 & 86 are energized the Com and 87 are a closed circuit and while the coil is not energized the com and 87A are closed. So yes, you could add another relay but as it is now when the relay is energized your LED is Off. If it's all the same power then you could power the LED from another source as well as the current source. Meaning your LED can be powered by more than a single line.

Ron

 

What are the voltages of all the signals?

 

Put a second relay across the contacts of the first relay.