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  #11  
Old 10-09-2013, 06:40 AM
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Bill.Peyton Bill.Peyton is offline
 
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The Plane Power alternators use the field voltage, as measured at the alternator field terminal, as the sense voltage. As Vern describes, if your field voltage is to low, the alternator will be fooled into thinking your main buss voltage is also low. When this situation exists, the internal PP regulator will command the alternator to output a higher voltage to the buss. This will then trip the over-voltage crowbar, which is internal to the alternator, when the alternator output exceeds the per-determined value. The crowbar does this by SHORTING the field terminal to ground thus tripping your breaker.
One thing to note, the Vertical Power creates a tiny voltage drop through the unit due to the way it switches. You will never see the field voltage at the same level as the buss voltage when you use the VPX system. This small voltage drop at the field output terminal will cause the PP alternator to regulate . 2-.3 volts higher then if you connected the field directly to the buss. If the (Ask me how I know) This in no way is a bad thing, just something to note.
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Last edited by Bill.Peyton : 10-09-2013 at 06:45 AM.
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  #12  
Old 10-09-2013, 08:00 AM
Acrophil Acrophil is offline
 
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Location: GA
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Default Great Resource

Thanks guys. I have printed this out and will spend tomorrow trouble shooting. Will probably get the guys at PP on the line as well.

One other question. The VPX has over voltage protection as well as the PP. Are they working together, in series, independent of each other or does PP need to be disabled or should I just be grateful for dual protection?
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  #13  
Old 10-09-2013, 04:09 PM
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Bill.Peyton Bill.Peyton is offline
 
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They are independent of each other.
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  #14  
Old 10-10-2013, 09:11 AM
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lostpilot28 lostpilot28 is offline
 
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Interesting thread...my PlanePower alternator was doing something similar - random breaker trips for no apparent reason. The alternator finally died after 210 hours in service, and I sent it in a little over a month ago. Plane Power was great to work with, and covered my repairs under warranty even though I was well outside of their coverage.
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  #15  
Old 10-10-2013, 04:02 PM
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Bill.Peyton Bill.Peyton is offline
 
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The reports on VAF don't seem to indicate a high reliability with the plane power alternators.....
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