Community Forums

Damon92 · 01-01-2013, 09:28 PM

I have a 1992 Damon Challenger DP. It has one engine battery and one house battery. I just bought an inverter to run tv and fridge and I think that would drain a single battery when boon docking. I also put a 160 AMP alt on her. My questions are:

1. Should I hook up a 2nd house battery parallel? Since there is an isolator between the 2 batteries on it now, I should still be safe from draining starter battery?

2. Will I be hurting or helping my alternator by adding a 2nd house battery?

3. Current House battery is 6 months old. Is that too old to mate with new battery?

Thanks!

RV Wizard · 01-02-2013, 01:59 AM

If the house battery you now have checks good on a battery tester you should have no problem adding a 2nd (like) battery to the equation. I would also recommend you do add a battery, connected in parallel to the house battery already in the coach. It will not harm the alternator as long as it and the others do not short out internally. Good luck and keep us posted.

monkey · 01-02-2013, 08:28 AM

RV Wizard is much smarter than me on these things,, but I agree ... Like he said, make sure the extra new house (coach) battery is the same as what you have now, so they have the same 'charge' rate... Hook it in parallel, pos to pos, neg to neg.. You'll need that for an inverter...

TdogKing · 01-02-2013, 09:14 AM

I'm in the process of adding a second 12 volt battery and a small inverter to my Class B. the isolator will take care of separating coach and chassis just like it always has, alternator will charge just the same. Make sure and use the correct size cables for the battery and the inverter, when in doubt bigger is better. RVSolarElectric.com has good information all about what your doing . It's where I bought my inverter years ago for my Class A.

Gary RVRoamer · 01-02-2013, 11:54 AM

Depending on the size of the inverter and the load on it, even two batteries can run down really quickly. The inverter has to pull 10x as many amps from the 12v batteries as it supplies for 120v output, plus at least an extra 10% penalty for effficiency loss in the process.

Tony Lee · 01-02-2013, 06:15 PM

The more info you give us the more useful will be the advice you get.

Boondocking - just an occasional night, or a week at a time.

Generator on board?

Any solar?

Running a furnace all night as well or just fair-weather boondocking?

Other loads? TV, sound system, lots of lights, microwave, coffee machine???

Size of existing battery in Amp hours?

What size inverter and what else do you plan on running off it.

How do you charge the existing battery? Just from the alternator when driving? Decent three-stage mains charger or fixed voltage converter?

Damon92 · 01-02-2013, 10:08 PM

Thanks for the replies. My batteries now are charged by alternator or converter when I am plugged into shore power, or generator (4K Onan). The inverter is a Charles Marine 1000 watt pure sine wave. I am planning to hook up inverter to one of the batteries with #2 gauge cable with a 150 AMP fuse to protect it.
I use my rig to tour with my band and seldom boondock and thanks to Mr. Buddy heater I have only used the furnace once. The inverter is primarily for down the road power for fridge and tv. I haven't considered but may use for microwave some. I have no solar.

If I add a 2nd coach battery in parallel can I just hook inverter leads to one of those batteries? Or go neg to one and positive of other? I may be over thinking!

Mr_D · 01-02-2013, 10:20 PM

Quote:

Originally Posted by Damon92

Thanks for the replies. My batteries now are charged by alternator or converter when I am plugged into shore power, or generator (4K Onan). The inverter is a Charles Marine 1000 watt pure sine wave. I am planning to hook up inverter to one of the batteries with #2 gauge cable with a 150 AMP fuse to protect it.
I use my rig to tour with my band and seldom boondock and thanks to Mr. Buddy heater I have only used the furnace once. The inverter is primarily for down the road power for fridge and tv. I haven't considered but may use for microwave some. I have no solar.

If I add a 2nd coach battery in parallel can I just hook inverter leads to one of those batteries? Or go neg to one and positive of other? I may be over thinking!

Good idea with the pure sine wave inverter. BUT, 1000 watts probably won't run your microwave unless it's a really low powered unit and then only if it's the only thing drawing power from the inverter.
We have a 2000 watt and it's just adequate.

Gorlininc · 01-03-2013, 01:34 AM

Adding batteries is a great idea. If you have 2 batteries now, I presume they are both 12 batteries. What I would do, if these 2 batteries are in good shape I would make them both the chassis batteries and hook them in parallel . Then buy 2 or 4 ( depending on space) 6 volt deep cycle batteries for the house batteries. You would hook 2 batteries in series to make 12 volts. This would give you great capacity.
Good luck on your travels
Rick

Damon92 · 01-03-2013, 12:33 PM

The microwave to me is not worth upgrading the inverter. I just don't use it that much. I would like to stay with the setup I have because even if my chassis battery dies I have an override switch for the isolator that allows me to draw from the coach side of things. (Cummins doesn't like the cold) Im looking at adding 1 more deep cycle 12 v to my coach bank. My question is if I have 2 coach batteries....which one should I hook my inverter to and does it even matter?

Thank y'all!

Gary RVRoamer · 01-03-2013, 03:38 PM

One battery can't provide adequate current for a large inverter for very long. The voltage will quickly drop and the inverter will shut down. Hook them in parallel so that both batteries can supply current when the inverter runs. While going down the road, the alternator should supply amps nearly as fast as they get used.

Gorlininc · 01-03-2013, 11:30 PM

I agree with the above.

Happy New Year
Rick

Mr_D · 01-03-2013, 11:59 PM

I've thought about adding a couple extra 6 volt batteries to the four we already have. There's room on the tray if I move the two chassis batteries. Would have to build new mounts behind the frame and in front of the rear cap. Both of them are 1000 CCA batteries and weigh a bunch. Doing that would only add 115 amp hrs to the rig (232 amp hours/2 (since they're 6 volts)/2 since you only want to discharge them 50%. For our use the gain probably wouldn't be worth it.

Gorlininc · 01-04-2013, 01:20 AM

Hi Mr D

You would gain 50 percent more usage. The real question is how often do you dry camp. I thought about the same thing. But I realized I don't dry camp that much or for very long. Either way you have a generator you can turn on to charge the batteries you have. My conclusion was it was not worth it to me. Unless one other reason. If you have a residential refrigerator. Then it may be worth it, if you plan on dry camping.
That's one mans opinion.
Rick.