Every RV owner should have a digital voltmeter permanently installed to monitor the condition of the coach batteries and their charging system. The minimum is a Lascar EMV 1200. http://www.alliedelec.com/catalog/catalogpages/2002/510.pdf
It is around $25 and installs with only two wires.

My preference is the TriMetric, which is close to $200. It is much more than a voltmeter. It can save you money by longer battery life and will even help you get by on fewer batteries if you boondock. We boondock exclusively and I use a CPAP, so battery life and capacity is important to us. I get from 7 to 10 years out of a set of batteries, so the TriMetric is worth it to us. I have seen way too many RVers suddenly have battery trouble and have to buy over-priced and/or less-than-ideal batteries while on a trip. The TriMetric we have was purchased two RVs ago, and has stayed with us as we upgraded. It has payed for itself in both money and convenience.

http://www.bogartengineering.com/

One other essential is a hydrometer. NAPA sells a good one with a temperature compensation.

A good site for battery info is:

http://bart.ccis.com/home/mnemeth/12volt/12volt.htm

and:

http://www.phrannie.org/battery.html

and:

http://www.trojan-battery.com/Tech-Support/BatteryMaintenance.aspx

and:

http://www.uuhome.de/william.darden/index.htm

[This message has been edited by bill h (edited June 03, 2005).]

Thanks Bill. Looks like I'm off to NAPA for starters, I mean Hydrometers, I know ...well you get what I mean.

God Bless

Bill; Should I have two? One for house batts. and 1 for engine batt. ? JKB

quote:

Originally posted by SLOOP JOHN B:
Bill; Should I have two? One for house batts. and 1 for engine batt. ? JKB

One for the house battery is a necessity, as it is always being run down and charged and so forth. A voltmeter for the engine is nice, but not as necessary, as the engine battery does not get as much cycling. Additionally, the instrument panel might have a voltmeter already, as most P32s do. They will not be as accurate, but are OK, especially if you are familiar with how it normally reads. But a voltmeter on the engine battery can be handy in detecting problems like overcharging or alternator failure.

There is another way to go:

You already have a cigarette lighter for the engine battery. You may have one for the house battery, such as in the TV antenna amplifier panel. Or you may want to put in a few here and there for different accessories. The Lascar meter can be connected and attached to a cigarette lighter plug(picture on request), and used for both. Heck, it can be moved from car to car to check on your whole fleet or to help other people.

BTW, the Chinese digital voltmeter cigarette lighter plug sold by CW and others is a piece of junk. I have had several.

Now that song is in my head for the rest of the day.



[This message has been edited by bill h (edited June 02, 2005).]