It is our first year using a radio power module (RPM) and our coms fluctuate every time we use it. Usually, we power the radio with the VRM, but the ports on the VRM are being taken by the 4 CANcoders we need for our MK4 swerve modules. Does anyone know why the RPM is causing coms to fluctuate? Is there a way to wire the CANcoders without the VRM so that we could use POE just incase we can’t get the RPM to work?
We used the RPM last year and for our off season bot and had no issues.
You might double check your wiring and make sure there are no stray wires and that they are fully inserted into the connectors.
The second part of your question.
CANCoders are a sensor so very low amperage and the can be part of a custom circuit that the rules are pretty relaxed on. You have options on how to power them. If you have a free PDH/PDM slot then you can use appropriate sized wires with an appropriate sized breaker. I would recommend getting a small one 5-10 A. Then you can splice the wires once you are away from the PDM/PDH. I would recommend something like these,
WAGO 221-415 Lever-Nuts 5 Conductor Compact Connectors 10 PK (amazon.com), but you can do it with just solder and electric tape if you feel comfortable with that.
You can use more than one VRM if you have a spare.
Rev makes another mini power module that is great for this type of stuff
Mini Power Module - REV Robotics
Came here to say this. Nothing preventing use of a second VRM!