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P-Mag Test Switch with VP-X and Skyview

N804RV

Well Known Member
Anyone running dual P-mags with VP-X and Skyview?

I'm thinking of just using the VP-X page in Skyview instead of wiring a discreet test switch to test the P-Mag self-powering capability.

The other option I was thinking of was a "normally closed" push-button switch just above the "Mag" switch that would momentarily interrupt bus power to the P-mag.

What have others done?

I'm ready to cut my panel now. But, can't decide.
 
I'm using a G3x to control the VP-X, but am doing the same: No dedicated switch to cut power to the PMags, just use the soft controls in the VP-x to test their internal power.
 
Same here. Less clutter on the panel. I go into the VP-X page, scroll down to each P-Mag circuit and do the ON/OFF test at <1000 RPM as a part of my pre-takeoff checklist.
 
I have switches

I use the VPX to test for self power. But I have 2 switches that I use for testing mag drop of each at runup. Works for me.

 
I have two switches for power and two for testing mag drop. Even though I have the VPX and the Skyview, I wired it all directly to the battery bus. No VPX involved in powering the PMags. Runup, check the mags, and then switch all the ships power off while at 1700 RPM and see that they power themselves. This is how I'm wiring my new Bearhawk build as well
 
I am installing two pmags this week and I'm in the same situation! I really dont want to clutter up the panel either! So I'm guessing you guys cleared out two dedicated 3 amp circuits on the VPX for the Pmags? This will require me to bunch up some of my other accessories and a considerable amount of rewiring. I have considered coming off one of my other circuits with both and then installing an inline slowblow fuse to each mag.
 
Yes 5.22. I wired per figure 1. Just 2 switches that remove power totally from each Pmag. I test rpm drop with these switches at runup. And test the self-powered feature by cutting power on the VPX, periodically.
 
I use 4 switches for my VP-X/SkyView/Dual PMag setup. One individual switch for each power & Ignition, in L IGN - L PWR - R PWR - R IGN sequence. That way, I can turn off PMag power together, but the ignition switches are separated to avoid doing it to them!

A couple of tips for the SV/VP-X/Pmag combination:
Use DPDT switches and you can connect the spare pole to SkyView's EMS and have a record of switch state on your datalog. This can be handy for troubleshooting an ignition problem if needed - or something as simple as marking an event, cycle one ignition off for a couple seconds to be able to see the point on the datalog.

You can also connect a spare EMS input to the PMag Ships Power input on the PMag and record whether the PMag is powered, either from the aircraft, or internally. If you then turn the PMag ships power off in flight, you will get an EMS alarm (and datalog record) if the internal generator were to fail.

You can see the effects of both on the screenshot, the 4 green dots on the bottom right.
32198454734_64fea542cf_c.jpg
 
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