We are testing an capacitive fuel level sensor in field. Its mounted on top of a heavy construction vehicle (colmar) with a 24v battery system. Our sensor runs for few weeks and damages. Every time a particular track is damaged together with all the components (mcu+sensor) following that track. So far we have only found a potential ground loop, but the track (burning repeatedly) is tested for up to 12amp continuous current. And if it had been a high voltage surge it should burn other tracks and component as well.
- nothing except marked in red is damaged
- track in red box is evaporated. Only that portion of ground track, as if some heavy current passed from battery-negative to chasis ground.
- Vehicle under question is a heavy duty digging machine, with all sorts of electrical noise.
Is it possible that a ground voltage variation between a) battery-negative and b) chassis-ground could develop, capable of burning 10-12amp rated PCB track? Even in that case, why rest of the circuitry following that track will get damaged?
Let me recheck battery configuration with field engineer, this way their is a constant 12v difference in my negative and chasis ground. I hope input is taken from another battery. battery checked I was wrong, correct topology updated now.