Monday, February 11, 2013

House battery

8AM - MsTioga's house battery
This morning we were straightening out the control wiring that we wrote to you about a couple of days ago. The control wiring is light gauge and connects the battery to the:
  • Morningstar Battery Charge Controller 
  • Trimetric Battery Monitor
  • Power Plus Leveler Controller
  • Xantrex Inverter Controller

If you have trouble understanding what all this stuff is, don't worry yourself about it. I installed it all and even I am bothered with understanding how all this is hooked up and operates. Anyway, while disconnecting the wiring in order to unravel all the wires, the cable that connects the solar battery bank with MsTioga's house battery dropped down and was not visible. As a result, I did not re-connect this cable!

The house battery is a marine type, a combination 12 volt starting battery and deep cycle battery. MsTioga's house battery is in poor shape and does not maintain a charge for longer than five minutes. In fact, the house battery only works because it is constantly robbing power from the solar battery bank. The house battery should have been replaced a long time ago. But being the slacker that I have become, I failed to replace it!

When the house battery lost its charge, MsTioga's interior lights went out. The refrigerator shut down because its 12 volt control power was no longer available. And I became confused because with all of this wiring, I did not realize that the jumper from the solar battery bank to the house battery was just lying on the floor, unconnected!

Not realizing that the disconnected jumper was the problem, I began to check anything that might have gone wrong. I cleaned the battery cables. Checked the disaster fuse that blows out if the battery bank should become shorted. Checked the power of the battery bank with a volt meter. Finally, by a process of elimination, I finally found the disconnected jumper!

The bottom line is, that the marine house battery should be replaced right away. We intend to drive back to the LTH Customer Service Center this morning, and buy a new marine battery.
Battery bank with straightened out control wires


Explanation of MsTioga's electrical system
When MsTioga was new, she came equipped from the factory with two batteries. One was the engine starting battery. The other is the house battery. These two batteries are isolated from each other. Both batteries receive charging voltage from the engine's alternator.

The house battery provides 12 volt DC electric power to the RV interior lights and appliances. The house battery may also be used to start the engine by depressing a special switch and simultaneously using the ignition switch.

When MsTioga's solar battery bank was installed, a cable connecting the solar battery bank to the house battery was also installed. This cable allowed the engine alternator to charge the solar battery bank when the engine was running. Also, the cable allows electric power from the solar battery bank to charge the house battery.

It has been suggested by readers that the original house battery should be removed. We tried this removal solution several years ago. But this solution proved to be a big problem. When the husse battery is removed, no 12 volt DC power is provided to 12 volt interior lighting or 12 volt appliances. Also, the engine may no longer be started from the removed house battery.

There may be a way to re-wire the 12 volt DC system so that the solar battery bank replaces the original house battery. But we have chosen to simply leave the 12 volt house battery in place. This method has been working well for us for several years.

59°F
Low marine clouds





Location: Los Pinos RV Park
Elevation: 950 meters