I'm working on a schematic for a power supply system for several linear actuators. I would like to minimize the power supplies needed to run the system. Can the source used to switch a relay be the same as the source for the load on the relay? I don't think so, the eStop in the diagram below isn't rated for the load on the relay. eStops aren't designed for high current. In the schematic below it seems like the estop would be exposed to the current draw of the load. Just want to check my assumptions. Thank you!
Can relay source and switching source be the same?
Any particular reason you are switching ground instead of +12 V?
No reason in particular. Is there a downside to one way or the other?
No problem, should a source terminal not be grounded (either +ve or -ve e.g. as in an automobile).
Should a source terminal be grounded, switching the ungrounded side is a must to prevent an earth fault from switching on a load.
Here's the conventional circuit that would also be okay for negative ground.