Battery Capacity & Tray Size

[lonestarace]

Hi Everybody:
We have a new to us 42' 99 Monaco Exec. tag w/3000w Trace Engineering inverter system w/RC7 remote control. This is all fine and dandy except: 1) the house batteries only consist of two 12v group 27 deep cycle lead acids, and 2) the house battery tray only measures 20"w, 17"d, 12"h. That's not much battery or room.

Suggestions Please?

Thanks in advance!

Don, Lisa, and Alexa

[Happycarz]

It originally came with (4) 6 volt golf cart batteries arranged as in the picture.

[RJay]

Yep, the batteries shown in the above picture are Interstate U2200 6 volt deep cycle batteries. L = 10.25, W = 7.12, H = 11.12. Ah/20hr = 225amps.

[wa8yxm]

I see RJay has given you the specs for the GC-2 class batteries (By the way you can often get GC-2 size batteries at Sam's or Costco for LESS)

COnfigured as in the photo you get 450 amp hours, or about 225 usable (That's over 2, thousand watts of power)

Think of the 4 batteries not as 4 batteries but as 2 pair
Each pair, electrically looks like this

-{Bat}+-{ery}+

And you think of that pair as a single 12 volt battery.. So drawn out your hook up looks like this
|-{Bat}+-{ery}+|-To House fuse panel, generator and converter
|-{Bat}+-{ery}+|
|-To Chassis ground

| is a battery cable

Very nice hookup.. I'll get there.. sooner or later

[lonestarace]

Thanks for your input, but we decided to break all the rules with our house batteries.
.
Instead of discarding the two deep cycle group 27s that are only 4 mths old, we added a third deep cycle group 27(different brand). This filled the 20" width, but left a 20" by 5" empty space on the tray. We found a Exide 12v this size at Tractor Supply, a group 3EE. So, now we have a battery tray full of new 12v batteries, and are only out $225 including extra battery cables.

We are going boondocking Saturday nite and will see how they hold up now. We boondocked last Saturday and it wasn't long before the we were down to 50% remaining. We have also learned to turn off the inverter unless we actually need it for 110V.

Don, Lisa, and Alexa

[rex]

Hope that Exide battery you got at Tractor Supply was a deep cycle.

[lonestarace]

It's may not be and that worries me. It says "Heavy Duty Commercial & Farm"? I put it on the outside, of the tray and it's the last one hooked up in parallel, just in case. It has a reserve capacity of 100 min. The other 3 batts have RCs of 160, 160, & 182, for a total of 602.

[wa8yxm]

One of the issues is you are giving us Reserve Capacity

What you need to know is AMP HOURS. Though there is a casual relationship.. it is not etched in lead, er, stone.

[nodine]

Originally Posted by lonestarace

It's may not be and that worries me. It says "Heavy Duty Commercial & Farm"? I put it on the outside, of the tray and it's the last one hooked up in parallel, just in case. It has a reserve capacity of 100 min. The other 3 batts have RCs of 160, 160, & 182, for a total of 602.

The biggest problem I see with what you are doing is that batteries connected in parallel are not of the same age, same manufacturer, and same type. If you experience one of the batteries using more water than the others then you have an imbalance problem. When non-identical batteries are connected in parallel one of them will feed on the others so to speak. Your set up will work, but it certainly is not optimized.

Bob

[lonestarace]

So far, so good.

The wx was perfect. Hi of 75, and low of 65. We started boondocking Sat.at1pm. We still had 90% when I got up this morning(Sun.) to start the coffee maker with the inverter.

We are learning how to manage this coaches batteries and complete 3000w inverter system. It's hooked up to everything except the roof airs. WOW! We love it, but we sure didn't know how to manage it at first. Our other coach only has a 400w partial inverter system on a 4 group 27 house batteries(Trojans). The only 110v stuff hooked up to it is the Sat. receiver, positioner, 26" LCD, & DVD. To brew coffee in the morning, I either had to use a little 12v coffee maker, or fire up the gen(noisy).

Mistakes we made last week were: 1) leaving the inverter on all the time, 2) letting the Norcold 1200 run off the inverter because we didn't know we could put it in MANUAL LP, 3) also, we accidentally left the Sat. receiver and a 110v cooling fan on in an overhead cabinet. These mistakes killed the 2 group 27s darn quik last weekend.

When and if our 4 current house batteries give us any grief, I'll install either 4 golf cart batteries or two group 4Ds.

Again, THANKS!

Don, Lisa, and Alexa