Community Forums

Dan McMartin · 06-03-2017, 05:31 PM

Considering ordering a residential fridge in our Bay Star. I'm well aware of the pros and cons, how they work, etc. My questions is this. If charging batteries off the generator and considering, in the Bay Star anyway, the res. fridge used it's own battery bank, does it take any longer to charge that it would without the separate battery bank?

In other words, I know the generator provided far more power than is required to charge batteries. Does each bank have a separate charger and so, therefore, they charge separately? Or do they share a single charger and charge as a single bank, taking more generator time to charge?

I hope the question makes sense. Really just wondering how charging time compares between the two set ups.

Lug_Nut · 06-03-2017, 05:39 PM

I'm not aware of a separate bank being used for the frig, however, if it is, it would be charged parallel to the house, probably through an isolator.
The residential frig is the way to go. Unlike the frig's we grew up with today's are very energy efficient. Great choice!

Peter

GaryKD · 06-03-2017, 05:51 PM

Hi Dan McMartin,
4 coach batteries, pure sine wave inverter is what one gets. The batteries are connected together. They are depleted and charged together.

twinboat · 06-03-2017, 06:02 PM

The specs say separate 1000 watt inverter and 2 EXTRA batteries.

I read that to mean they add 2 batteries to the 2 standard installed ones, creating a larger capacity, single bank.

To your question, with a larger bank, you may need a longer charging time or charging more frequently.

The converter listed is a 45 amp model. See if they do or can upgrade that to 55 to 60 amp output. That could shorten your generator run time.

Dan McMartin · 06-03-2017, 06:13 PM

Honestly, I'm not sure about how the batteries are set up. I know that without the res fridge you get two batteries in the engine bay.

I also know that with the res fridge you get four batteries and from what I've seen, they are all in a tray mid-coach. I don't know if they are all wired as one bank or not. I would seem logical but what do I know?

I'll probably begin the process of replacing batteries and adding solar on day one. I that means upgrading a charger or something, so be it. Honestly, I need to get my hands on the coach to see how its wired.

sedaliaterry · 06-03-2017, 06:21 PM

Twinboat is correct. Our 3113 has 4 12v batteries in parallel. There is 1 1kw inverter dedicated to the residential fridge and another dedicated to the tv's and certain outlets.

Dan, all 4 house batteries are in slide tray in bay behind LP bay on drivers side as you indicate. Only 1 chassis battery is in engine bay.

As far as charge time on the string, it will obviously take longer to charge a 4 battery string that is depleted (down to 12v or 50% charge) than a 2 battery string. I have been told as much as 2-3 days on shore power by dealer (not sure I buy that but...). I expect gen would be no different (no matter what the real charge time is), because it should be powering the same charging system.

I did find out I could run the fridge on battery/inverter for at least 1 day and still have 12.5v left on the batteries. I am thinking they may go 2-3 days before charge point is hit. I plan to test when I get back from current trip.

JMH · 06-03-2017, 07:04 PM

Charge time will depend on the output of the generator and your chargers capabilities. For our battery bank (8 AGM) the generator/charger buts out more amperage than the bank can absorb. So, our batteries will charge at the same rate no matter how many, up to 8, are in the bay.

So, check you generator output amperage, and your chargers rated charging capacity (remember the generator is rated in amps 120VAC and the charger is rated 12VDC so with out conversion the numbers may be confusing). If the charger can charge at the maximum absorption rate of your batteries then you are maxed out.

How long it will take to charge is now another question. That depends on you batteries and their ability to absorb over time. I'd ask Newmar for data.

cc8375 · 06-03-2017, 07:10 PM

In our CS3940 we have 4 - 6 volt batteries in a slide tray and 2- 6 volt batteries under the hood next to the chassis battery.
I have gone 3. 5 days on running the Fridge without a re-charge. I am not sure how long it takes to recharge these batteries.

vsheetz · 06-03-2017, 07:41 PM

Common to have two additional battery with RR option. They are all in the same house battery bank and all charged together.

My coach was four batteries without, six with, the RR option.

Dan McMartin · 06-03-2017, 07:53 PM

At least the battery layout is confirmed. One bank. As far as charging time, I'm just trying to decide if generator runs would become excessive. Don't want to be running the gennie 12 hours a day just to run the fridge the other 12 on battery. I'm guessing 4-5 hours a day or so might keep the batteries happy for at least a few days of boondocking, maybe more. Manageable until we add solar.

And this all might be a moot point since we plan to install at least some solar pretty quick.

I really need to actually get a MH so I can stop all this theoretical BS and start actually doing something