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Topic: House battery voltage and converter (Read 490 times) previous topic - next topic

House battery voltage and converter

As my inverter/converter is not charging my batteries, it still seems to be converting shore power to DC.  What would be the lowest safe voltage on the house batteries before damage is done?
Thanks for the help.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: House battery voltage and converter

Reply #1 –
Quote from: Yetch –
As my inverter/converter is not charging my batteries, it still seems to be converting shore power to DC.  What would be the lowest safe voltage on the house batteries before damage is done?
Thanks for the help.
Mike

Mike,

Need more explanation. "Converting shore power/120 VAC to DC" IS, repeat IS battery charging.

If lead acid or AGM batteries, 12.2 VDC is as low as you want to take them for long battery life.
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: House battery voltage and converter

Reply #2 –
The voltage is showing between 12.35 and 12.5.  The charging mode of the Heart25 will not work.  If I turn the charge mode on, the red light remains on, and voltage stays at that level.  With the mode function off, same thing.  I have put a charger on the batteries, and voltage will go to 13.3 to 13.5.  When I remove the charger, voltage eventually goes back to 12.35 to 12.45 and remains.
I am assuming the Heart 25 is providing that voltage through the batteries.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: House battery voltage and converter

Reply #3 –
Time to replace the Heart 25. It has lasted a long time.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: House battery voltage and converter

Reply #4 –
I would think that is what your batteries are at. Nothing to do with your inverter.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: House battery voltage and converter

Reply #5 –
Yes, am ordering a Freedom 458 model 81-2530-12.  I was told this would utilize the Link 2000 interface which is what I have, and would pretty much be 'plug and play'.  Is anyone familiar with this unit, and have any comments?  I would appreciate comments or criticisms on this choice.
Thanks for the help.
Mike
 
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: House battery voltage and converter

Reply #6 –
Quote from: Yetch –
Yes, am ordering a Freedom 458 model 81-2530-12.
I would appreciate comments or criticisms on this choice.
Mike,

The Freedom 458 is a modified sine wave inverter.  IMO, since you going to the trouble of installing a new unit, I believe you would be better served by choosing a pure sine wave model.  Just my opinion.

https://www.xantrex.com/power-products/inverter-chargers/freedom-458.aspx



1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: House battery voltage and converter

Reply #7 –
I agree with Chuck.  Going with a pure sine wave will cost you more, plus cost of adding the new display but I think in the end you will be way happier, along with all of your equipment that is using the inverter.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: House battery voltage and converter

Reply #8 –
When I installed the Magnum 2812 the new controller display fit where the old display
was  and I use the old control wire. I had to do a small modification to the old rack
for the Magnum to fit. With  the modern electronics you need a pure sine wave inverter.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: House battery voltage and converter

Reply #9 –
Quote from: Yetch –
I have put a charger on the batteries, and voltage will go to 13.3 to 13.5.  When I remove the charger, voltage eventually goes back to 12.35 to 12.45 and remains.
I am assuming the Heart 25 is providing that voltage through the batteries.
Mike

Mike I think you need a quick lesson in battery voltage, battery charging, and making assumptions.

Measure your battery voltage after a 3 hour rest.  24 hours is better, but three hours works in the real world.  12.5 to 12.7 volts is fully charged.  12.2 is 50% state of charge and the lowest you should drain lead acid batteries.

The reason for the resting period before measuring voltage has to do with the chemistry of lead acid batteries.  The final chemical reaction of the three chemical reactions involved with charging and discharging lead acid batteries takes about 24 hours to complete.  After 3 hours it's mostly done and we aren't going to fuss over less than 1/10 of 1 volt.

If your current charger inverter was doing anything to keep the batteries charged you would be measuring 13.2V.  That  is a good voltage to keep the batteries from self discharging.  13.6V is a good slow charge from 80% state of charge to full, and 14.4V is good from 0 to 80% state of charge.

And finally, reach a little deeper into your pocket and purchase a pure sine wave inverter.  There are enough people on this list qualified to talk you through any problems you might have with the installation and the electronics in your modern toaster will thank you.

Art
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: House battery voltage and converter

Reply #10 –
EDECOA 2500W 5000 Watt Power Inverter Pure Sine Wave 12V dc to 120V ac LCD...

 I have used 2 of these . No problems and good price . 

 My charger ," Currently" in use.;    PowerMax 110 Volts AC to 12 Volts DC 60 AMP PM3-60 RV Converter | eBay
  Seems to work fine  on my cheap LA batteries.