12 v from car?

[harrtenn]

When your camper (2002 Coleman Cottonwood-new to us) is hooked up to the TV (plugged in etc.) does that mean your camper is now on the 12 volt side? I'm asking for refrigerator purposes because I don't want to propane on while driving down the road (it makes me nervous.

[waterdoctor]

When your camper (2002 Coleman Cottonwood-new to us) is hooked up to the TV (plugged in etc.) does that mean your camper is now on the 12 volt side? I'm asking for refrigerator purposes because I don't want to propane on while driving down the road (it makes me nervous.

Harrtenn
If your PUP is set up like mine, the TV battery power is routed directly to the converter in your PUP (for recharging your PUP battery(ies). The power then flows to the PUP circuits, and ultimately, to your fridge, if it's set to run on 12Vdc. I assume you have a 3 way fridge. Also, there should be a battery disconnect near your PUP battery, generally on the tongue. So, in a sense, yes, once you plug into the TV, some of the TV power is running the fridge. Just make sure to set the switch on your fridge to 12Vdc and turn off the propane and 110 Vac.  I'm sure there will be others who chime in on this, but this is how my 2000 Coleman is set up.  Hope this helps.
Steve :U

[harrtenn]

Yes the info is very helpful (we don't have a battery on the tongue though PUP didn't come with it and we didn't buy one yet. It is wired for it though.

[waterdoctor]

Yes the info is very helpful (we don't have a battery on the tongue though PUP didn't come with it and we didn't buy one yet. It is wired for it though.

In that case, I wouldn't rely on my TV battery to last very long cooling the fridge if the TV isn't running. Standard car batteries just don't have the amp hours of power storage to keep things running very long without stranding you somewhere. You pretty much have to have the TV running to keep enough power in the batt to turn the engine over. I would encourage you to get a marine battery and set your PUP up for that. Since you're already wired for the battery, it shouldn't be a big deal. I assume you have a converter onboard the PUP so you can also plug into 'shore power' (or a generator) when you're camping. All the lights in the PUP are 12Vdc and the converter takes the 110 Vac shore power and converts it to 12Vdc. You might need to get a battery box and mount it to the frame. On mine, I have a metal tray that's welded to the frame in front of the propane tank. The batteries (I have 2) are in their own individual boxes and are held in place with bungee cords. Some folks here have changed over to 6V golf cart batteries, hooked together (in series, I think) to get the 12V, but have the advantage of over 200 Amp hrs of power storage. There are some postings in this forum that address the golf cart battery scenario. Hope this helps.
Steve :U

[flyfisherman]

You have to have a "hot wire" running from the tow vehicle to the pup in order to use the vehicle's battery. In my case, I ran a hot wire from the battery  (with a fuse in between) and connected it to the center post in a 7-pin connector. It allows me to use the camper's overhead lights. In the case of my previous pup which had a furnance which would be connected as well.



Fly

[oreo57]

First youll need to find out if the TV is wired for 12v to the plug on the TV, if it is you can still run the fridge on 12v without the battery connected as long as your hooked to the TV, But rember to disconnect when ever you stop for any exteneded period it will drain the TV battery in a couple of hours.
 
Also make sure the wires for the battery if not installed aren't touching each other or anything else

[austinado16]

Wire up a 7 pin round like this:


Wire up a 6 pin round like this:

[coach]

[SIZE="3"]Some vehicles come from the factory with a pre wired charge line that is only hot when the ignition is on. That is the correct method to wire a charge line, large enough wire for the expected load.

If you pre cool you fridge with 120v or propane, the contents will stay cool for a long time (insulation). If the charge line is working, the fridge will operate from the 12v supplied by the vehicle alternator (fridge set to 12v).

A volt meter can be used to determine if pin 4 is hot (either wiht the ignition on or off).[/SIZE]

[tlhdoc]

Some vehicles come from the factory with a pre wired charge line that is only hot when the ignition is on. That is the correct method to wire a charge line, large enough wire for the expected load.

My TV came prewired and the "hot" line is always hot.  Not just when the ignition is on.  

[wavery]

My TV came prewired and the "hot" line is always hot.  Not just when the ignition is on.  

Coach said, "Some vehicles come from the factory with a pre wired charge line that is only hot when the ignition is on. That is the correct method to wire a charge line".

The operative words is "correct". It may have been better to say "Best".

It's just a matter of installing a relay in the charge line. They are available at most auto parts stores. You just cut the charge line close the power end (in some cases, the battery others will be the fuse box). Both sides of the cut wire go to the relay and another hot line, that only works when the ignition is on, goes to the 3rd lug on the relay. Power only flows to the charge line when the ignition is on.

******Note of caution******...........It's best to use the "accessory" lug on your fuse panel for your "ignition hot" power source. Just tapping into any line that is "Ignition hot" under the hood could mess up the readings on your vehicles on-board computer.

[tlhdoc]

The operative words is "correct". It may have been better to say "Best".

If you want to be able to have power to the trailer from the TV (ie: camper battery is dead and you need to use a small amount of 12 volt power) and you don't want to leave a key in the TV, it would not be the best way to have the hot line wired.  I the winter, when the camper battery is in the house, it is nice to use the TV to provide power for the camper lights.  The lights are LEDs and only draw a small amount of power.

[wavery]

If you want to be able to have power to the trailer from the TV (ie: camper battery is dead and you need to use a small amount of 12 volt power) and you don't want to leave a key in the TV, it would not be the best way to have the hot line wired.  I the winter, when the camper battery is in the house, it is nice to use the TV to provide power for the camper lights.  The lights are LEDs and only draw a small amount of power.

Sorry Tracy....I still (respectfully) disagree.......:sombraro:

IMO, the protection that some can recieve against an accidental dead battery far outweighs the benefits of using the the camper battery with the engine off. Even with a small drain. Maybe not to you but certainly to most people. That's why I still think it's "best" (for most). :sombraro:

However, if someone wanted it both ways, a simple toggle switch could be added to over-ride the relay. In fact, I think that I've seen realys with a switch built in.

[GlennS]

Basic 12V relay info is here:
     http://www.the12volt.com/relays/relays.asp

The main page, //www.the12volt.com, has a wealth of information.

Wavery is correct to use a relay that is connected to only allow 12V from the TV when it is running. However, I think you'll find that most automotive relays have 4 or 5 terminals, see first 12volt link above for information on correct connections. The relay coil gets connected to an "accessory" terminal, the other two terminals between the TV battery/fuse panel and the PUT 12V battery line.

One other thing: when you select the 12volt line on the TV, do make sure it's a fused line, and that the fuse doesn't protect anything critical. You wouldn't want a  failure of your PUP refrigerator to kill your TV headlights! Most vechicles have spare fuse locations in their fuse boxes. If you can use a spare for your PUT connection, and fuse it appropriately, you should minimize risk to the TV circuits. And use appropriate sized wire for the amount of current your fuse allows.

I do agree with Coach that a hot-only-when-the-TV-is-on is the correct way. The first time you run your TV battery down because you forgot to shut it off (and you will, sooner or later) you'll wish you never connected it that way. It's a bear to push-start the TV with your PUT behind it!

Glenn