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Old 07-13-2012, 03:27 PM   #1
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1978 31' Excella 500
Lowndesboro , Alabama
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outside battery question

We recently purchased a 78 Excella and when my husband went to unhook it from our vehicle the switch wouldn't work unless we plugged the camper into an electrical source. Apparently our outside batteries don't work. The previous owner always kept it plugged in to an electrical outlet. What are the outside batteries used for and should we replace them before we go camping in 1 week? Will we need the outside batteries if we're plugging it in at the campground to the electrical outlet?
Thanks for any help!!
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Old 07-13-2012, 04:05 PM   #2
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1977 31' Sovereign
1963 26' Overlander
1989 34' Excella
Johnsburg , Illinois
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If the converter (univolt) is working properly, you can camp, as long as you are plugged in. However it is advisable to buy at least one battery to level out the spikes produced by the old style converters.
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Old 07-13-2012, 04:13 PM   #3
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1973 21' Globetrotter
Houston , Texas
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I have heard that the Univolt (converter) was designed to work with a battery, and that using one without a battery will result in its premature death. So, if this is true, you will definitely want to replace the battery.
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Old 07-13-2012, 04:35 PM   #4
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The coach battery powers the emergency breakaway switch.
Click on the link to see a picture of the Sioux River falls near my home.
Eastern South Dakota is very pretty with hills, rivers, and trees.
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Old 07-13-2012, 04:42 PM   #5
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1976 Argosy 28
Alamo Heights , Texas
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No one directly answered your question about what the batteries are used for.

First, and most important from a towing safety perspective, the onboard batteries provide power for the breakaway switch that will apply the brakes if the trailer comes unhooked from your tow vehicle. This is a fairly unlikely scenario, but would put you in a bad liability position if it happened and the trailer did any damage or injured someone.

The battery provides power for the whole 12v system when you're not plugged into campground power. Depending on the age of your refrigerator, it may require 12v power for the control board even if you're using propane or 120v power to actually chill the refrigerator. The 12v system also powers all of the lights inside your trailer, the water pump that's used if you're using the freshwater tank instead of a campground connection, any vent or exhaust fans built into the trailer and (as you learned already) the electric jack.

If you plugged the trailer in and the jack worked again, and if the interior lights work when the trailer is plugged in but not otherwise, then the Univolt (or some replacement converter-charger) is working for now and it'll work on shore power. As already mentioned, the original converters weren't designed to work properly without a battery in the system, and you may get higher voltage than you expect on the 12v system, or varying voltage.

For the breakaway system alone, batteries are essential to have to tow legally.
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He has all of the virtues I dislike and none of the vices I admire. — Sir Winston Churchill
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Old 07-13-2012, 04:58 PM   #6
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1988 32' Excella
Robbinsville , New Jersey
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Check at the batteries for power before replacing them in case there is a switch to turn off the batteries or a blown fuse.
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Old 07-15-2012, 04:55 PM   #7
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1978 31' Excella 500
Lowndesboro , Alabama
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Thanks everyone for you're help. We found out the batteries are 2 years old so my husband is going to replace them before our trip this weekend.
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Old 07-15-2012, 05:13 PM   #8
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2005 19' Safari
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Suggest you check the batteries to make sure they are full of electrolyte; then charge them and have them load tested. (Most auto parts places will do this for free; e.g., AutoZone, Pep Boys, O'Reilly's, etc.) There is a good possibility the batteries are OK, and replacing them may be an unnecessary expense.
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