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Topic: coach batteries (Read 434 times) previous topic - next topic

coach batteries

if i put generator in auto mode it runs for about 4 hours then shuts down sitting there watching tv on sat and gen will restart around 45 min later i'm presuming the batteries are not hold good voltage. I can just drydock and never lose the inverter for over 8 hours. 
anybody have an opinion whats going on.
brian eichhorn
2001 u20 34'

Re: coach batteries

Reply #1 –
 What do you have your inverter cutout set at? The auto start only comes on when voltage gets below 12.2
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: coach batteries

Reply #2 –
Quote from: bvectra –
if i put generator in auto mode it runs for about 4 hours then shuts down sitting there watching tv on sat and gen will restart around 45 min later i'm presuming the batteries are not hold good voltage. I can just drydock and never lose the inverter for over 8 hours. 
anybody have an opinion whats going on.

Without knowing amp-hr capacity of the batteries, their age/condition and what loads you are running, even a GUESS could be way off in left field.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: coach batteries

Reply #3 –
As Craneman said you first need to know what voltage the batteries have when the generator stopped and also what Wolfe said.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: coach batteries

Reply #4 –
Quote from: craneman –
What do you have your inverter cutout set at? The auto start only comes on when voltage gets below 12.2
What Craneman said is key here.  If you're running lead acid batteries of any flavor, flooded, Gel or AGM, their chemistry is sluggish.  As it is, the voltage will drop while under load and then bounce back while resting.  As we see here, under load the battery voltage may drop below the generator auto start voltage set point and begin charging, long before you have reached a state of charge that would require a charging cycle.

Or you have dirty connections, or your batteries are s**t.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: coach batteries

Reply #5 –
Some auto starts had preset cut in points.  Not adjustable.  Not sure if they have a delay built in to compensate for quick short loads. 

 I would test the batteries to see their condition?

As an example a  networked Magnum auto gen start is adjustable.  Some are not
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: coach batteries

Reply #6 –
The factory Dynogen auto start on my coach has adjustable voltage and delay.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean