Battery voltage too high for inverter?

[zombk]

Hello all, I'm new to RVing but have had my fair share of DIY projects. Currently I'm a bit stumped. My two inverters are reading over-voltage on my house battery. One inverter is rated for 12VDC input with 120VAC output with 2000W constant and 4600W peak and its over-voltage light came on. My second inverter is rated for 12VDC input 120VAC output at 1000W constant and has a voltmeter which read 15 volts. I checked the battery with my multimeter and it read 9.6 volts. The on-board voltmeter installed by the previous owner (an electrical engineer) reads 14.1 volts.
I'm guessing my multimeter is messed up or has low batteries as the other three pieces of equipment read much higher voltage. So is there any way to step down the voltage from the battery to an inverter? Any and all recommendations are welcome!

[mojoman]

I think the over voltage light is for the 120v side. Your batteries can't over voltage unless they are wired for 24v or your battery charger/converter is providing over 14v. Is this a new RV?

[zombk]

No, the RV is not new, it's a 93 Roadtrek but the RV battery is just about brand new. I was thinking it's possible the big ol' Dodge 360's alternator may be pushing out high voltage, and with the house battery being in new condition it may be a couple volts high.

On my older inverter (with the built in voltmeter) it was reading Incoming voltage at 15V before pegging out. I know a fully charged brand new car battery can fully charge up to about 14V.

Do most people not put inverters in RV's? It seems like a cheap and easy solution to a generator.

[mojoman]

Take you rig to a auto supply store and they can check your charging system and batteries for free. To check your multimeter, check the voltage on your other vehicle or neighbor's battery that has just ran (fully charged) it should read 12.8v.

[briancummings]

We use many Inverters in our company Oilfield units and I have seen plenty of them show over voltage and in most cases the Inverter will shut down until the incoming voltage drops to within it's prescribed limits, this voltage limit varies depending on manufacturer. I personally had 2 that would shut down if the incoming voltage got above 14.8 vdc. We went to a different manufacturer that had higher voltage limits and have not had the problem any more.

[zombk]

Thanks Mojo, I appreciate it! I'll take it to an autozone in the next couple days.

[zombk]

Thanks for your input. I'll have the alternator checked out and if everything is fine then I'll try stepping the voltage down by about 1.5 volts and see how it works.