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Topic: Battery Charging (Read 776 times) previous topic - next topic

Battery Charging


  I want to charge the staring batteries and the house batteries in my coach before waking it from its winter sleep.
  Can I hook a battery charger up to the connections on the Battery isolator located under the bed?
  The starting and house batteries are not easily accessible on this 2003 U320.
  I did a search and I am confused and do not want to damage the electrical system.
              Thanks--Jim
Jim & Doreen
2003 U320

 "Too often I would hear men boast of the miles covered that day, rarely of what they had seen"
― Louis L'Amour

Re: Battery Charging

Reply #1 –
Why not just plug into shore power with your 50 amp cable or use an adapter into a 120V outlet if no 30 or 50 amp available? I plug a trickle charger into a coach outlet (in my wet bay) and then go into the electrical (the engine battery lug) bus just a few inches away so as soon as I plug into shore power, both house and engine batteries charge.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Battery Charging

Reply #2 –
Will your generator start?  pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Re: Battery Charging

Reply #3 –
I, too, have a 3820 coach and those starter batteries are a challanged to acess.  As Pierce suggested, just plug into shore power with either a 50 or 30 amp source. Activate your "boost" switch and let it do it's thing overnight. No shore power, use your genset, get it warmed up, too.

No RV! Have hung up the keys.
In the past: 2016 Winnebago Era, 1994 Foretravel U240, 1995 Foretravel U240 (wide body), 1999 Foretravel 320, 36 Foot, 2003 Foretravel U320 38 foot,

Re: Battery Charging

Reply #4 –
  Thanks, Unfortunately I have no shore power at the storage location and the batteries have been disconnected since mid December.
  I thought it would be best to at least give them a charge with an external battery charger before trying to start onboard
  generator.
  I have a Honda EU2000i and the EU2000i Companion but have been unsuccessful in using the 30 amp adapter to get A/C
  power to the coach. I don't know if the onboard Prosine Inverter/Converter or built in surge protection is preventing A/C power
  to be supplied by the Honda's.
          I have an external Progressive EMS-PT50C which shows all ok from the Honda's.
 
  I know some have trickle chargers or battery tenders hooked up to the isolator and I would like to know if I can connect an external battery charger to the isolator without doing any damage.
            Thanks--Jim

 
Jim & Doreen
2003 U320

 "Too often I would hear men boast of the miles covered that day, rarely of what they had seen"
― Louis L'Amour

Re: Battery Charging

Reply #5 –
I do not have an answer to the question about the isolator. But, if the batteries were fully charged when put in storage. And by disconnected you mean the negative post to the batteries were disconnected. Then the batteries, after storage of only three months, should still be almost fully charged. I would simply test them with a volt meter. Then if showing a good charge, start the generator.
Larry and Terry
Ex 2004 U270 36'

Re: Battery Charging

Reply #6 –

  Thanks--Yes they were fully charged before I disconnected the negative cables from both battery banks.
  Hopefully the house batteries will be in good enough condition to start the generator.
              Jim
Jim & Doreen
2003 U320

 "Too often I would hear men boast of the miles covered that day, rarely of what they had seen"
― Louis L'Amour

Re: Battery Charging

Reply #7 –
If you are talking about the 30 amp plug on your honda that could be a 240 / 120 volt plug and you would have to make up your
own adapter. For charging you batteries just use the 15 amp 120 volt receptacle, those adapters are available in any RV store.
I would just try and start you generator, you won't hurt the batteries. It will either start the generator or not. Same thing with the engine. The best thing  is to keep them charged up and in your case go out and run you generator once a month. Don't forget to
load up your generator
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Battery Charging

Reply #8 –

  Yes, that sounds best.
            I will hopefully start the generator, charge up the batteries while taking a nice 2 hr round trip.
                            Thanks all for your help,  Jim
Jim & Doreen
2003 U320

 "Too often I would hear men boast of the miles covered that day, rarely of what they had seen"
― Louis L'Amour

Re: Battery Charging

Reply #9 –
Two hours will not fully charge your batteries.  Hopefully you can drive it to a location you can plug the 50 Amp cable into for power, then give it another 4-8 hours approx, depending on condition of the batteries.  Would expect they are not going to recover to a healthy condition.

Re: Battery Charging

Reply #10 –
Quote from: Dave M –
Would expect they are not going to recover to a healthy condition.

Dave,

Even though they were fully charged first, then disconnected for storage?  We routinely do this with my car and our golf cart for the summer (longer than the 3 months the OP had his coach in storage) and neither have had a problem. 
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Battery Charging

Reply #11 –
Michelle,  Good point, however I seem to have gotten the idea they were nearly dead, unable to start either the ISM nor the genset with the boost feature.  I do wish everyone good luck.

Re: Battery Charging

Reply #12 –
If the batteries are disconnected at their posts, they will go through the entire winter without losing anything if in good shape. A very cold battery will not provide the CCA but the voltage will be close to when it was disconnected. Summer with high temperatures and humidity will discharge a battery much faster. Anyone watch the Diehard Battery ads with the battery encased in ice? It does work that way and a fully charged battery won't freeze. You just can't turn off a switch. The batteries have to be disconnected at their posts.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Battery Charging

Reply #13 –
Pierce is right and disconnecting 1 battery may or may not have the batteries disconnected.  Seems there is mass confusion around battery connections.

Re: Battery Charging

Reply #14 –
 :headwall:  ok so my coach and engine high price shutoffs at the rear of rhe engine bay don't count for storage? Your correct, I'm confused...

Battery cables to the switches then to engine, then to inverter, 12v panel.. is because the posts come to one point and the terminal voltage could ve different?
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My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)
 

Re: Battery Charging

Reply #15 –
Topic has drifted from answering OP's question.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320