Battery charging

[margeleept]

Hi, I have a few questions about battery charging. I have a "new" 2004 Casita LD 17. I do have a charging system monitor and my goal for the weekend is to get to know it. But here's my quesstions:

1. How do I tell if I have the older convertor that can overcharge the battery? The Casita book says that the Parallax 7300 or 6300 are the old ones.
2. I assume that the battery cutoff switch has to be "on" in order to charge from the car when driving?
3. Is it possible to overcharge the battery when driving all day?
4. If plugged in to shore power, how long does it generally take to charge and how long before it overcharges? Is it really that sensitive that I have to worry about it much?

Thanks for your thoughts!

[stevebaz]

If your battery charger isnt smart and you leave the charger on you can cook your battery. once your batter gets to 12.7 volts your battery is considered charged.

While charging from the car while driving the voltage regulator in your car becomes your smart charger and regulates how much power is being put out. i have never heard of anyone over powering the trailer batteries if the system is working properly.

If you want to stop being the daily monitor to your battery charging then I would upgrade to a better charging system for your batteries.

If I were you I would call best converters and talk to them about an upgrade.

Magnetek/Parallax 6300/7300/8300 Upgrade Kits

[Byron Kinnaman]

Originally Posted by stevebaz

If your battery charger isnt smart and you leave the charger on you can cook your battery. once your batter gets to 12.7 volts your battery is considered charged.

While charging from the car while driving the voltage regulator in your car becomes your smart charger and regulates how much power is being put out. i have never heard of anyone over powering the trailer batteries if the system is working properly.

If you want to stop being the daily monitor to your battery charging then I would upgrade to a better charging system for your batteries.

If I were you I would call best converters and talk to them about an upgrade.

Magnetek/Parallax 6300/7300/8300 Upgrade Kits

If you read battery specifications that fully charged voltage will be 13.8. But don't depend on cheap volt meters to read accurately.

[Paul O.]

Originally Posted by Byron Kinnaman

If you read battery specifications that fully charged voltage will be 13.8. But don't depend on cheap volt meters to read accurately.

I think there is some confusion here. I think he meant 12.7 Volts is the fully charged no load battery voltage. That is what I look for when I check my battery with a voltmeter. The 13.8 Volts is more likely the alternator or charger output, which will measure anywhere on the 12V circuit.

[Jon Vermilye]

The only time an accurate voltage measurement will show the actual state of charge of a battery is when all charging sources are disconnected (or shut off), and the battery has "rested" i.e. sat without charging sources for an hour or so. You can skip the wait by putting an amp or two load on the battery for 20 - 30 minutes, then disconnect the load, then measure.

During charging, depending on the solar controller / converter, voltages as high as 14.8 may be measured, depending on what stage the charger is in (Even higher if it is in the equalization mode). Most chargers float (the voltage output when the battery is fully charged) at 13.2V - 13.4V, so measurement while the charger source is active won't tell you much.