help engine control unit

hi all

im attempting to create a engine control unit for a RC aircraft with onbord start sequence for nitro engine. so far I have a good idea of the hardware required but there is one aspect that has me stumped.

im using Arduino mega, interacting with a relay board, but how do I tell if a circuit is live after the switches?

im supplying power to a glow plug 5v at 2-6 amps and I need some form of signal to go back to the arduino to detect is the glow plug is working or not before I send a signal to start a engine.

I was thinking of using another relay switch to do this but is there any other options

help and feedback would be much appreciated.

apc282:
hi all

im attempting to create a engine control unit for a RC aircraft with onbord start sequence for nitro engine. so far I have a good idea of the hardware required but there is one aspect that has me stumped.

im using Arduino mega, interacting with a relay board, but how do I tell if a circuit is live after the switches?

im supplying power to a glow plug 5v at 2-6 amps and I need some form of signal to go back to the arduino to detect is the glow plug is working or not before I send a signal to start a engine.

I was thinking of using another relay switch to do this but is there any other options

help and feedback would be much appreciated.

Well, you really answered your own question. If the current to the glow plug is zero, it's not working. If greater than zero, it is working. Search the forum for ways to measure DC current with an Arduino.

Paul