trailer batteries

[08ramguy]

Has any one every thought of or heard of any one or them selves hooked three 12V batteries up? I have two batteries in my current trailer but was curious if you could hook three up, would the generator charge all three if hooked up properly, is there away to hook all three up correctly?......I have a generic QP40, I would think that this gen has plenty enough power to charge all three.....

[Road-King]

You could wire as many 12 volt in parallel as you want. If you wanted to use 6 volt batteries you would need to use sets of two wired in a series than you could wire two set in parallel to each other. As for your genny, I don't know...

[PopBeavers]

Google "The 12 volt side of life". It has a great deal of information regarding the 12 volt system in an RV.

[RamblerGuy]

The generator makes 120 volt AC. Your convertor converts 120 volts AC to the 12 volts DC to charge your batteries and to supply the lights, refrigerator controls, fans, etc.

The battery charging rate is limited by your convertor capacity. For example, the generator on our Class C is rated for 4000 watts, which is 33 amps at 120 volts. The convertor is rated for 55 amps at 12 volts, which is 660 watts. The batteries will be charged with whatever 12 volt DC power is left after supplying the lights, etc.

[Herk7769]

Originally Posted by RamblerGuy

The generator makes 120 volt AC. Your convertor converts 120 volts AC to the 12 volts DC to charge your batteries and to supply the lights, refrigerator controls, fans, etc.

The battery charging rate is limited by your convertor capacity. For example, the generator on our Class C is rated for 4000 watts, which is 33 amps at 120 volts. The convertor is rated for 55 amps at 12 volts, which is 660 watts. The batteries will be charged with whatever 12 volt DC power is left after supplying the lights, etc.

While true on the surface, it is misleading when you imply all available power left after what you are using in the camper goes to charge the battery.

It does not. The charging circuits in the converter are "staged" and the converter reduces the charging "power" available to the battery by stages based on the charge level detected by converter.

The initial charging current for a very low battery (below 50%) is about 25 amps during the "Bulk Mode" first stage which could take about an hour depending on how badly depleted the battery is; then drops to about 8 amps during "Absorption Mode" which could take many hours to "soak" the electrons deep into the thick lead plates. Absorption Mode lasts until the battery capacity reaches 90%.

Then the final stage is a trickle charger (called "FLOAT Mode") that only provides about 100 - 800 (as it "tops off" over a few days) milliamps of charge regardless of camper power consumption to prevent battery boiling.

[RamblerGuy]

You are correct, but I only wanted to point out that the convertor's capacity is the limiting factor in recharging batteries, not the generator capacity.

[Herk7769]

Originally Posted by RamblerGuy

You are correct, but I only wanted to point out that the convertor's capacity is the limiting factor in recharging batteries, not the generator capacity.

Very true.