 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
ceengland7(at)gmail.com
Guest
|
 Posted: Tue Sep 15, 2020 6:53 am Post subject: Installed new battery, Bus voltage went up over 15volts |
 |
|
On 9/15/2020 9:22 AM, Bill Watson wrote:
| Quote: |
<Mauledriver(at)nc.rr.com>
I am running a Z-14 electrical system with dual batts/alts/buses. I
recently changed out an old Odyssey 680 for a new one after 4+ years
of service because it's fully charged, no load voltage fell to 12.5
volts. I swapped the battery positions as I put in the new one per my
normal procedure.
On the 2nd leg of the first flight after the swap I noticed that the
bus with the new battery was running slightly over 15 volts. Normally
it runs between 14.5 and 14.7. After some switching of avionics and
other components, I took it off line.
Is there any obvious reason a new battery would cause a bus to
suddenly run at a higher voltage when at cruise and presumably the
power is being supplied by an alternator and the voltage controlled by
an B&C regulator? 15 volts is too high a charging voltage for an
Odyssey per their user doc.
My inclination is to adjust the regulator but I don't recall having to
do this with past battery changes or swaps (the regulator is really
hard to access so there's that too).
Thoughts and opinions welcome.
Bill "everytime I get comfortable with a system something new pops up"
Watson
Seems unlikely that the battery change would cause it, but easy enough
|
to verify, if you still have the old battery. Just return everything to
pre-replacement configuration & re-check.
--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
 |
jluckey(at)pacbell.net
Guest
|
| Posted: Tue Sep 15, 2020 9:50 am Post subject: Installed new battery, Bus voltage went up over 15volts |
|
|
Bill,
Thinking out loud here:
The only way to get voltage that high is from the alternator (kinda obvious) and the thing that controls the alternator is the regulator (again, obvious) therefore we might concentrate on the regulator. (I know, brilliant deductive reasoning 
I'm not familiar with the B&C regulator but I think it has a voltage-sense terminal. Any chance something weird happened with the sense lead? If the regulator is not getting accurate voltage signal it might over-control the field??
Anecdote:
A few years ago a friend has a similar but not identical problem. The master had been left on and drained the battery. The battery was removed and charged for an hour or two outside the airplane. He re-installed the battery and flew the plane and the voltage went crazy and fried his avionics stack ($$ouch!$$). There was no over-voltage protection module.
We have never come up with a scenario that explains the failure. (This is probably due to incomplete information regarding the details of the event. I don't have first-hand knowledge of the details, so when we discuss it over beers, the details get a little "fuzzy".)
I'm interested in some/any hypothesis that might explain that behavior. It might be relevant to the situation at hand.
-JL
On Tuesday, September 15, 2020, 07:35:13 AM PDT, Bill Watson <mauledriver(at)nc.rr.com> wrote:
--> AeroElectric-List message posted by: Bill Watson <Mauledriver(at)nc.rr.com (Mauledriver(at)nc.rr.com)>
I am running a Z-14 electrical system with dual batts/alts/buses. I
recently changed out an old Odyssey 680 for a new one after 4+ years of
service because it's fully charged, no load voltage fell to 12.5
volts. I swapped the battery positions as I put in the new one per my
normal procedure.
On the 2nd leg of the first flight after the swap I noticed that the bus
with the new battery was running slightly over 15 volts. Normally it
runs between 14.5 and 14.7. After some switching of avionics and other
components, I took it off line.
Is there any obvious reason a new battery would cause a bus to suddenly
run at a higher voltage when at cruise and presumably the power is being
supplied by an alternator and the voltage controlled by an B&C
regulator? 15 volts is too high a charging voltage for an Odyssey per
their user doc.
My inclination is to adjust the regulator but I don't recall having to
do this with past battery changes or swaps (the regulator is really hard
to access so there's that too).
Thoughts and opinions welcome.
Bill "everytime I get comfortable with a system something new pops up"
Watson
--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
http://www.matronics.com/Navigatonbsp; - MATRONICS WEB FORUMS -http://wiki.matronics.com[/url]
http://www.matron===
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
