Can you plug into 120 while the 12v batteries are out?

[Cam A]

The deep-cycle batteries are out of the trailer right now, as I try to resuscitate the batteries that came with the trailer. Can I plug into 120 while the 12 volt circuit is incomplete? The battery capacities differ (740 vs 800); is this an issue?

[Darwin Maring]

Yes you can, just be sure the battery cables are not shorted together or the + cable does not touch the frame (Ground).

If there is a fuse on the + cable just pull it out so it can not be shorted.

[Frederick L. Simson]

Yes you can, just be sure the battery cables are not shorted together or the + cable does not touch the frame (Ground).

If there is a fuse on the + cable just pull it out so it can not be shorted.

I do this all of the time when the trailer is in the back yard.

[Roy in TO]

The deep-cycle batteries are out of the trailer right now, as I try to resuscitate the batteries ... The battery capacities differ (740 vs 800); is this an issue?

I'm waiting to hear the answer on this.
Are the #'s you give the CCA (Cold Cranking Amps)?
Are they 12 V batteries? If so and if they are dead have you considered getting a pair of 6V golf cart batteries? You'd get more life and Amp hours from a pair of those than regular 12V.

[Cam A]

I'm waiting to hear the answer on this.
Are the #'s you give the CCA (Cold Cranking Amps)?
Are they 12 V batteries? If so and if they are dead have you considered getting a pair of 6V golf cart batteries? You'd get more life and Amp hours from a pair of those than regular 12V.

I think it's cold cranking amps, and they are 12 volt. One is dead, so I will be replacing the existing 12 volt. If you went the 6 volt route, would your converter handle it?

[Frederick L. Simson]

If you went the 6 volt route, would your converter handle it?

Using 6 volt Golf Cart batteries should only be done in pairs, and they must be connected in Series like each [b]pair of [b]RED batteries in the example.
This produces the equivalent of 1 giant 12 volt battery.

The [b]GRAY batteries in the example are 12 volt batteries which must be connected in Parallel.


Banks of 4 batteries. Use just the top 2 to get banks of 2 batteries.

[Ed Harris]

To continue what Fred said just a little, It is also a good idea to replace the 12v batteries in pairs.
If not when charging the new and old batteries are likely to not allow a full charge to the bank either.

Also it is fine to run the 120v A.C. without any batteries on board as long as you make sure the leads are separate as noted above.
You will get better 12v regulation with batteries but should have no real problem without.

[Orlen Wolf]

Lots of good advice here but I would advance a caution on powering 12v accessories from the converter when the batteries are disconnected, especially with older converters. Many older converters have poor 12v regulation so, with no batteries attached, the 12v lines can rise to 15 volts or higher. Your 12v lights won't like that very much.

[Elvin Lowe]

Actually, the converter in the 2002 Casita runs up to close to 20 volts without a battery.