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PMag tripping on VP-X

#74430

Member
Hi Guys,

My Dual PMags are tripping the on the VP-X after a few seconds. If I reset them I can quickly crank the engine and them they hold power.

If I do a MAG check by switching the key between L/R/BOTH they also trip and remain off, although the Mags obviously still work due to their internal power generation.

I'll have to recheck what AMP I set them to on the VP-X (each on their own breaker), but is there something else I should be doing to correct this?

Thanks,

Dan
 
Current fault detect maybe?

Is the current fault detection for that circuit set to YES or NO?
While flying, I had an issue with with my heated Dynon Pitot that has a controller.
VP-X current fault detect was set to YES for the Pitot Heat, and after 3 - 4 minutes (the controller probably limiting the current, regulating the probe's temperature), VPX would trip, thinking there was a fault...
When resetted, it would work for another 3 minutes or so, then trip again, and so on...

Tested the wiring and switch (all ok), re-configured VP-X to NO, problem gone !!!
 
Be aware that the VPX triggers on peak rather than average current like a conventional thermo breaker. Be sure the value is set high enough to prevent tripping at peak current.

Items like coils have very high peak current for a very short time period but rather lower average current.
 
I believe that the Brad recommends using physical breakers and not running through the VP-X so that you can have a dedicated power wire just for the PMags. Might be something to consider.
 
In the Manual

What amperage have u set your VPX breakers at for the P-Mags? VPX manual has a specific setting. In the VPX install manual 5-22.
Mine have been operating properly per suggested settings from first start.
 
Maybe a fuse ... ?

Ha, the same reason I drive my truck into town instead of using a horse-drawn carriage... modern technology isn't bad; just needs to be understood. Having said that, fuses work fine if that's the electric model you designed your airplane around. But it's not helpful for someone who's already bought and installed an electronic circuit breaker system.
 
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