VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 05-12-2019, 04:42 PM
bob888 bob888 is offline
 
Join Date: Jul 2012
Location: Fresno, CA
Posts: 232
Default High voltage

My charging voltage shows 14.9 - 15.1 volts in cruise flight. I have the standard Vans 60 amp internally regulated PLane Power alternator. I guess the question is whether this is a problem or not. Electrical system seems happy so far. I assume the voltage reading is correct; G3X engine monitor.
Reply With Quote
  #2  
Old 05-12-2019, 04:57 PM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 1,967
Default

Yes, this is a problem.

Suggest you first connect a simple multimeter and verify your engine monitor is accurately reading buss voltage (you need not run the engine, just compare the readings). If so, repair or replace the alternator.

Carl
Reply With Quote
  #3  
Old 05-12-2019, 08:37 PM
CDN CDN is offline
 
Join Date: Nov 2011
Location: Calgary, AB
Posts: 102
Default Plane power alternator

You've already received the correct advice of verifying with a multimeter.

On a side note the 60 amp plane power alternators have not been enjoying a great reputation for reliability. A survey on here indicated that about 1/3 of them fail with less than 300 hours. Mine failed somewhere around 240 hours. I had it repaired by a local autoelectrics shop. So if you feel the need to remove it any automotive alternator repair shop should be able to bench test it for you.
__________________
VAF Donation made Feb 2019
RV-10 C-GNCX Flying and LOVING IT!
Reply With Quote
  #4  
Old 05-12-2019, 08:55 PM
pilot2512 pilot2512 is offline
 
Join Date: Aug 2007
Location: Spring, TX
Posts: 392
Default

Voltage is measured as a reference to ground. Verify your engine/alternator are properly grounded.
__________________
Jay
RV-9A
Empennage complete.
Wings complete.
Fuselage in progress
Wiring in progress
2018 Donation made!
Reply With Quote
  #5  
Old 05-13-2019, 02:52 AM
BobTurner BobTurner is offline
 
Join Date: Dec 2011
Location: Livermore, CA
Posts: 5,662
Default

IIRC (and itís quite possible I donít) the internally regulated PP senses buss voltage off the field circuit line. Make sure there are solid connections, low resistance CB, etc, on that line/connection, too.
Itís almost as if you have one diode worth of voltage drop in that line.
Reply With Quote
  #6  
Old 05-13-2019, 05:59 AM
BillL BillL is online now
 
Join Date: Sep 2007
Location: Central IL
Posts: 4,926
Default

Quote:
Originally Posted by pilot2512 View Post
Voltage is measured as a reference to ground. Verify your engine/alternator are properly grounded.
Quote:
Originally Posted by BobTurner View Post
IIRC (and itís quite possible I donít) the internally regulated PP senses buss voltage off the field circuit line. Make sure there are solid connections, low resistance CB, etc, on that line/connection, too.
Itís almost as if you have one diode worth of voltage drop in that line.
Two excellent suggestions as the place to start.
__________________
Bill

RV-7
1st Flight 1-27-18
Phase II 8-3-18
Repairman 11-15-18
Instrument Currency 12-17-18
Shrunken Exit = ??
No Photo? => PM me.
Reply With Quote
  #7  
Old 05-13-2019, 07:04 AM
Bill.Peyton's Avatar
Bill.Peyton Bill.Peyton is offline
 
Join Date: Sep 2009
Location: St. Louis, MO
Posts: 1,678
Default

Before you convict the alternator, verify that you do not have a significant voltage drop across the field wire. As pointed out in an earlier response, the voltage regulator uses the field terminal to determine the regulated voltage. If the field wire, CB, or switch, has too much resistance, a voltage drop will develop across that path, which will result in the VR thinking the voltage is too low and increase it's output voltage. The first step would be to measure the voltage drop across the path of the field circuit. You could also remove the field wire and temporarily run a new 18 gauge wire from the battery to the field terminal and run the engine and see if that fixes your issue.
Having said that. My PP alternator lasted less than 400 hours before it was replaced with a Band C.
__________________
Bill Peyton
RV-10 - 950 hrs
First Flight Oct 2012
WA0SYV
Aviation Partners, LLC
Reply With Quote
  #8  
Old 05-13-2019, 10:50 AM
rdrcrmatt rdrcrmatt is offline
 
Join Date: Oct 2014
Location: Milwaukee, WI
Posts: 224
Default

Quote:
Originally Posted by Bill.Peyton View Post
My PP alternator lasted less than 400 hours before it was replaced with a Band C.
Do you have a link to purchase your replacement? I'm almost thinking of buying one for the shelf after this topic.
__________________
Matt
CFI / RV-10
Reply With Quote
  #9  
Old 05-13-2019, 10:54 AM
Lenny Iszak's Avatar
Lenny Iszak Lenny Iszak is offline
 
Join Date: Sep 2008
Location: Palm City, FL
Posts: 268
Default

Also check the connector at the alternator. Thereís an extensive thread about that.

If it ends up to be a failing regulator, hereís the Aircraftspruce part numberr for a replacement:
07-17968

Lenny
__________________
Lenny Iszak
Palm City, FL
2014 RV-10, N311LZ - 500 hrs
Reply With Quote
  #10  
Old 05-16-2019, 12:10 PM
bob888 bob888 is offline
 
Join Date: Jul 2012
Location: Fresno, CA
Posts: 232
Default

After reading all the above and checking accuracy of my voltmeter (within .2 of test instrument), I did what I should have done first. A review of the Odyssey spec sheet showed ideal charging voltage 14.7 and normal range 14.2 to 15 volts. I guess Iím OK... Thanks to all for their input.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 06:50 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.