CrossRoads:
Something like a ground fault interrupter but for DC circuits.
Or, monitor the current and if it exceeds the 5A level have a switch to cut out the source.
what I was thinking of doing somethign like the monitoring. Theres already going to be an arduino nano onboard that triggers the relay. Was just wondering if it would be better to use a fuse or somethign though rather then monitoring the amperage.