Charging the house battery

[CarlB]

has anyone taken a Greyhawk and modified it such that the house battery can get charged by the vehicle's alternator?

[hoppers4]

Your house battery is being charged by the alternator without any mods.

[CarlB]

If that is true then there is some very large parasitic drain on the house battery while driving.

Also if it is getting a charge, then running the inverter shouldn't be as much of an issue as it has been for us. After a few hours of running the TV on the inverter, it starts to yap about low voltage. Something is not right...

[jimp]

Possibly a bad battery, or low water in the cells???

[hoppers4]

I'm wondering if you don't have something messed up in that charging circuit. At the factory they have to install some extra goodies like a relay and more wiring to facilitate the aftermarket battery boost button. The charging path should be part of this wiring. The aftermarket stuff is easy to spot under the hood on the firewall. I know it's working on mine because when I start the rig the voltage on the inverter goes from 13.2 or 13.6 up to 14.2.

[us71na]

Originally Posted by CarlB

After a few hours of running the TV on the inverter, it starts to yap about low voltage. Something is not right...

How much wattage does your TV use and what is the ouput capacity of the battery in amp hours. You'll likely find that you are getting the full charge but it is being consumed by the "few hours" and losses in the inverter. Your inverter also uses power even when the TV is not on if the inverter is powered.

[CarlB]

When I get her back I will check the voltage display on the inverter after the truck starts. Previously we only used it while driving, hence my frustration and questions. We did have to replace the battery that came with the unit, and we just got used to using the gen set for power.

[DanNJanice]

CarlB,
IMO the single best investment you can make is a clamp-on DC amp meter. They are not real accurate say +/- 0.5amp, but good enough, especially if you zero them just before you clamp on.
The great thing about them is you can clamp onto the wires leading to your batteries without breaking the connection and immediately check things.
Like if it is charging/discharging.
If you have high parasitic loads.
How much current the various devices in your trailer actually are using, etc.

I purchased the meter below from Sears a couple of years ago and it has worked perfectly. Amazon also has lots of them, just make sure the DC portion is clamp on, not just the AC portion.
03473756000