What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Voltage reading thresholds

scrollF4

Moderator, Asst. Line Boy
Ambassador
For the collective brain trust,
I have 3 hours on my RV-7A's Phase I. Factory new Lyc IO-360M1B, PlanePower 70 amp alternator (yep, I do mean 70 amp). SkyView with EMS, and VPX.

The alternator charges the battery at a consistent 14.4 to 14.5 volts, with rock solid amperage recovery after start. Using SkyView's default voltage threshold settings, these volts are just barely into the yellow zone, which bugs me because I'm so much more partial to Green. :eek:

My questions:
1) Is 14.4 to 14.5 volts a normal and acceptable range, or too high?
2) What green/yellow/red voltage thresholds do you recommend for my Skyview settings?
 
I would ask this question to your battery manufacturer. Only they would know for sure.
 
Odyssey recomends 14.1 - 14.7 for optimum charge with a 15 volt limit, so my settings are something like:
Red - 0-12.5; 15- 16
Yel - 12.6 - 13.; 14.8 - 14.9
Grn- 13.1 - 14.7
 
Last edited:
...and I do indeed have an Odyssey (I should have mentioned that). Thanks Walt, that's just what I needed.
 
Here is a link to Odyssey Battery PDF. Below are some quotes from the manual.
The trickle charge voltage should be 13.5V to 13.8V.
Standard internal combustion engine alternators with an output voltage of 14.2V can also charge these batteries.
in deep cycling applications it is important to have the charge voltage set at 14.4 ? 15.0V. A nominal setting of 14.7V is a good choice
14.4 to 14.5 is slightly high, but acceptable.
And so the answer is, it all depends.
 
I have a PC680, actually my third one. The second one developed "blisters" in the side and eventually shorted a cell. This was due to forgetting to turn on my alternator and after 30 min of flying noticed the low voltage and turned on the alternator. I think the heave charging rate is what blistered the sides and resulted in a short. My third Odyssey has started doing this also and I had been charging at 14.7v so I've dialed back the voltage limit. Has anyone else had issues with the sides of the battery bulging outwards?
Marty, RV6A
 
I have a PC680, actually my third one. The second one developed "blisters" in the side and eventually shorted a cell. This was due to forgetting to turn on my alternator and after 30 min of flying noticed the low voltage and turned on the alternator. I think the heave charging rate is what blistered the sides and resulted in a short. My third Odyssey has started doing this also and I had been charging at 14.7v so I've dialed back the voltage limit. Has anyone else had issues with the sides of the battery bulging outwards?
Marty, RV6A

Interesting, the similar certified Concorde AGM Battery has a note in it's manual that bulging or caved in sides and ends are OK....:)
 
Back
Top