UPG 250 amp hour agm batteries

MNtundraRet wrote:
Many new units coming out with residential, but manufacturer's expect you be camped on an electric site, not boon-dogging.

I have noticed lately that some of the residential refer upgrades come with at least 4 EXTRA batteries (typically 6V) on top of the 4 for the other loads. Some even come with 4 extra 8D AGM batteries. And I've even seen some L16's offered.

Golden_HVAC wrote:

PS: I hope that you already know that high toque motors like a refrigerator require pure sine wave power, not the lower cost modified sine wave power. It might start fine with no load on MSW, but once it is cold, and the pressure is different between the cold side and hot side, starting current might increase a lot.

This statement is not supported by the many hundreds of people who have installed a residential refrigerator or the literally thousands of factory installed residential refrigerators all powered by a modified sine wave inverter.

Dave:

How many amps is the Residential Refer. drawing on a 1-hour duty cycle? Have you checked the amps being drawn from the battery-bank with a clamp-meter? They will be 10 times the 120v,ac draw when using 12v, dc.

I just purchased a new 1000 watt (2000 surge) inverter (10 year old 400 watt inverter just died) for my HD TV and 2nd amplifier (plus other temp. uses). The inverter does show "wattage" and "amps" under load, but "watt's" readout is inaccurate under 200 watts (per specs.). For the TV drawing less the 25 watts reading is zero. The reason I used the clamp-meter on the battery cable.

The reason I ask is that it looks like you expect to use the refer. 24/7 over a weekend, along with all other normal 12v needs. Using just two 75AH batteries does not seem doable, especially for having batteries hold up long-term.

P.S. I missed the comment about the generator, so you should be okay.

I would love to dump the RV refer. when they come out with energy efficient compressor refers. Many new units coming out with residential, but manufacturer's expect you be camped on an electric site, not boon-dogging.

Almot wrote:
Yes, if genny is to be run every morning, a bank of 250 AH will do. With that much load, I would still go up to 300 Ah. The beauty of 12V batts is that you don't have to keep an even number of them, like you would with 6V.

But this all still doesn't solve the problem of charging 2 different types of batteries - AGM and flooded - at the same time. Or maybe I'm wrong and there is no such problem.

I don't think there is a problem. You can use the same charger. My progressive dynamics charger works with both.

Yes, if genny is to be run every morning, a bank of 250 AH will do. With that much load, I would still go up to 300 Ah. The beauty of 12V batts is that you don't have to keep an even number of them, like you would with 6V.

But this all still doesn't solve the problem of charging 2 different types of batteries - AGM and flooded - at the same time. Or maybe I'm wrong and there is no such problem.

Almot wrote:

With the bank made of some AGM and some flooded, how are you going to charge them? Separately? I also doubt that your current 2*75 AH "will suffice for now", with 90-something AH daily draw from 120V fridge alone. You'll kill them in no time.

I am only a occasional camper and plan on using our Honda eu3000 as much as needed. The batteries only have to operate the fridge during the night. So far on three different nights the fridge has only used 200 watts. I disconnected the defrost. It has not been hot but the fridge alone should not be a problem. Of course I do want to run the tv and satellite a little! after generator hours.
With my current setup I think I will only have to run the genny a coupe hours a day max unless of course AC is needed.

I know my idea here is a little nuts to begin with just bouncing some ideas around. The upg advertisement says clearly these batteries can be mounted in any position also that they are totally sealed and can be used without worrying about gassing. So I imagine in the UPG battery case you should be able to mount the thing upside down if you wanted. Also called and asked on of the techs at Batterystuff.com and they backed all this info up. Now the question is can you trust this info.

My SIL AGMs have tubes vent hose fits over. My East Penn Deka's have valves where the fill caps would be, flush with the top. I double check they are not gassing when top charging by floating a little distilled water up there (in case any gets ingested which it should not, in theory). One bubble in a vent and I back something off.

AGMs can and do vent if over charged, or if fighting their way back from significant sulfation such as when being run flat. When my string was equalizing on float when new, I could see the stronger cells let go a bubble here and there as they cooked down to equal. That hurt lol!

Jim

I haven't seen installations with AGM on its side. Venting is not an issue with AGM, but they do have vents and I wonder where those are. Tried to find them on my 100 AH UPG and couldn't. Maybe they are under the label. Folks here at the forum gave me a slap on the hand and told not to look for something that I am not supposed to play with :), i.e. those vents. So make sure you are not laying it on the vents.

Weight... At 64 lbs I'd say 100 Ah battery is already too heavy, my neck spine is telling me this every time I lifting them. Especially when you have to lift it from some obscure nook between the trailer and propane tank, or from some box.

With the bank made of some AGM and some flooded, how are you going to charge them? Separately? I also doubt that your current 2*75 AH "will suffice for now", with 90-something AH daily draw from 120V fridge alone. You'll kill them in no time.

Very interesting stuff folks. I have another question. So lets say I get a smaller agm battery. Lets say a 100 amp hour. Because it is a agm I can lay it on its side right by my inverter (which by the way is a prowatt sw2000 pure sine wave) run two extremely short (less than a foot) 1/0 cables and connect directly to my converter. I also don't have to worry about venting because it is a agm. I will still have my other two vented interstates also connected to my inverter with separate cables. My question here is what is the downside of doing this. I all ready know it will bring down the life of the agm because it is newer than my smaller 75 amp batteries.

So will it be a catastrophic effect on the agm or will it be just somewhat shorter life.

Is there a problem with this set up not being in parallel with the other two batteries.

Would you trust the agm right next to the inverter unvented.

I have a 60 amp P/D converter charger, new last year. It is suppose to work fine with both agm and normal wet cell batteries. But will there be a problem with charging the batteries not in parallel.

Now please keep in mind my camper does not get much use. The max is about a month a year and usually we have hookups. I think solar is way cool but using that setup is way down the road for us as we use a Honda 3000 generator now for charging and AC. We don't plan on changing unless after we retire when our camper or future camper will get a lot more use. So keeping that info in mind and the fact that I am willing to let the newer battery take a reasonable hit in lifespan is what I suggest practical.