|
1999 American Tradition 40TVS
full timing and mostly boondocking
house batteries in bad shape, both terminal corrosion and extremely low on water. In fact, the four six-volt batteries took a full gallon of distilled water to top them off. I charged them by being plugged in to household 20amp service for about 4 days.
The three-step charger seemed to be operating properly, red to yellow to green as the batteries were charging. Using a temperature correcting hydrometer, I tested all four batteries after that and found two borderline good and two a little less than borderline. I decided to run them until they were unable to deliver proper service. It's been cold during the nights even though we are in St. George, UT so I turn the 7500-watt generator on for about an hour while I run both furnaces to heat the coach and then turn them off until it gets too cold for comfort. Last week we experienced a problem with the generator running, the light on the charger stayed red constantly and the 'charging bars' went from green to yellow followed by loss of a/c power from the inverter.”
This could be due to failing charger, failing batteries, or not charging lead acid batteries properly.
“I tested the house batteries again and found all four to be bad.”
Again, this could be due to failing charger, failing batteries, or not charging lead acid batteries properly.
Defective Batteries
I am not sure what testing bad means. Four abused batteries are likely to have widely varying specific gravities. Just adding distilled water can create stratification and may stay that way for a while when in use. Different cells may mix more than others. A short period of high voltage charging would cause the batteries to “boil” and result in mixing the distilled water and acid.
Low specific gravity means low charge level. The sulfur ion in the acid combines with lead to produce lead sulfate. Lead sulfate re-dissolves as charging progresses.
Lead acid batteries stored deeply discharged form sulfate crystals. If they fall off the plates, they take lead and sulfur ions with them to the bottom. This causes low specific gravity. There is no recovery from this.
Charging lead acid Batteries
It takes 14 to 18 hours to fully charge lead acid batteries. You charged yours for 4 days. That should be enough. However, running a generator, however high capacity, for an hour does very little to charge lead acid batteries. It often takes 4 hours on a high capacity charger to charge from 20% SoC to 80% SoC. Another 10 hours is required to finish the charge to 100%.
Failing Charger
For better advice, please supply make and model of charger. You probably have a combined inverter/charger. Lights on different charger systems mean different things. Do you have a manual for the charger?
Many RV’s have a set of bars that are supposed to represent state of charger (SoC). Most of these are only accurate in “static” state. Static means not charging for 3 hours or so, also not discharging significantly. Green dropping to yellow usually means discharging normally. It also means not charging.
Some RV’s have much better monitors. What is the make and model of yours.
Inverter/chargers often have circuit breakers on the device. They may have push buttons, or have fuses. There is probably a high capacity fuse or breaker in the wire from the inverter to the battery bank.
“I replaced all four with equivalent items and now when looking at the charger panel with the engine off and the generator off and no shore power connected the yellow light (normal) is on and green bars show on the charger panel indicating good battery voltage.”
If the batteries had not stopped charging before you installed new batteries, I would have guessed a fuse or circuit breaker may have tripped while the batteries were being installed. If you have a Magnum inverter/charger, it may have been damaged when the batteries were changed. Magnum specific procedures are required. However, whatever happened probably happened before you installed new batteries.
“However, as soon as I plug the shore power in the charger light turns red and stays that way throughout the entire night. If I unplug the shore power and start the generator the charge light immediately goes red and stays that way. If I turn the generator off and start the engine the charge light goes back to yellow and the green bars on the charger panel are green, and they even go a couple of bars higher indicating that the engine's alternator is charging very well."
We need the make and model of the inverter/charger to understand what the lights mean.
"I have rechecked the battery cable routing and there are only two minor wires hooked to the positive and negative terminals and they are not hooked up improperly. I'm not sure what to check next. Any help will be appreciated. “
I have no idea what this means. Can you post a picture?
“Standing voltage on the house batteries is 12.18 Standing voltage on the chassis batteries is 12.7 With the generator running the voltage at the house batteries is 12.18 still. So obviously no charging. There is a bright silver solenoid on the back side of the electrical box that has 12.7 volts at the bottom terminal and 12.18 at the top terminal, so I'm assuming this is the 'Auxiliary Battery Connect' solenoid. I'm not sure where the converter/inverter/charger is located.”
The inverter/charger is usually located near the battery bank, but not in the battery compartment. It may have a remote control panel inside the RV. A remote may have its own make and model visible on it. We may be able to trace the inverter from the remote specs.
__________________
Paul Bristol
Kodiak Cub 176RD
Nissan Pathfinder 2015
|
Linear Mode
