Traveling with Fridge running.

Discussion in 'On The Road' started by Electric Cowboy, Mar 6, 2015.

  1. goody59

    goody59 Member

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    You might find it strange but in Australia we tow our PUPs and similar with our gas bottles turned off and run our 3 way fridges on 12v DC. How strange is that. Enough said. I have expressed my views on this subject before. No need to rehash my past posts. I guess we all need to make our own risk assessments in our daily activities and act accordingly.
     
  2. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    I think most people with 3-way fridges do travel running on 12V.

    My first 2 campers were 2-way, propane and 120V. So after 15+ years of only having propane for teh fridge while traveling I have no concern. I do find I like propane better for long trips, it keep the food and freezer colder than the 12V.

    Also, I have found on long trips that TV battery charge line does not do that great of job while running 12V fridge. There is too much voltage drop. There has been several times, I arrived at a site after 6+ hours of driving and running the fridge on 12V to find my battery is discharged to somewhere between 12.2 to 12.5V. Not an issue if you arive at a CS with electric hook ups. But, It sucks if it's a dry camp site. I think you need a number 8 wire in the TV to solve that issue.

    So 75% of the time we travel with the propane fridge.
     
  3. goody59

    goody59 Member

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    I realise that running the 3 way fridge on 12.7V at the fridge requires a heavy duty dedicated charge line from the tow vehicle's alternator source rather than from the PUP battery that may have some insufficient charge going to it (The house battery in PUP) from the wiring harness of the tow vehicle. That 12v DC supply after voltage drop doesn't cut the mustard with a power draw of somewhere near 14 amps when the 3 way fridge running on 12v DC. But once you have wiring sorted, the reast is easy. You can run the fridge on 12.7v DC all day long.
    Another heavy duty dedicated charge line from the alternator of tow vehicle also ideal to have your house battery charging nicely as you drive. Dont have the house battery and the fridge power on the same circuit though as that means placing two loads on one circuit and results in both loads not having sufficient voltage to function efficiently. I used 25mm2 (or 4 AWG) cable for my dedicated power circuits and the same size wiring for the negative return to the battery of tow vehicle (or earth) too rather than chassis for earth. The cable is expensive but once it is done you have a great system. Don't forget to fuse your cables close to the battery source.
     
  4. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    So you run two charge lines to your TV? One for your camper battery to recharge and a dedicated line directly to the fridge which is isolated from the camper battery?

    I'm currently using all my pins on the seven pin connector, I have backup lights. Do you have a second connector at the hitch for the fridge line or are you using pin 7 in the connector for the fridge?
     
  5. goody59

    goody59 Member

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    Two dedicated lines with one load(house battery on one and fridge 12.7v DC on other) on each circuit. Works best using Anderson plug connectors between tow vehicle and PUP. Fuse both circuits close to the source battery and another fuse at the house battery.


    http://www.ebay.com.au/itm/50-AMP-ANDERSON-CONNECTOR-PLUG-COVER-EXTERNAL-MOUNTING-BRACKET-KIT-50AMP-50A-/400823400128?pt=LH_DefaultDomain_15&hash=item5d52efb6c0

    You are not going to get 25mm2 cable in anything else, especially a tow plug connector.
     
  6. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    Thanks, that make sense moving the circuits all the way back to the TV battery vs spliting them back at camper.
     
  7. lifespeed

    lifespeed Member

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    That is what I do as well. But I have an unusual setup with #8 wire and DC-input charger that charges (or maintains) the batteries regardless of the 9A fridge draw. 99% of the other pup-ers don't have such a setup so the battery drain issue with the fridge on 12V is a concern.

    I think proper TV and trailer wiring (probably 8G) would at least maintain charge, but a voltmeter measurement with the fridge on and TV running confirming at least 13.3V at the batteries would be needed to prove a successful implementation. I think most electrical setups are inadequate for this to work without a basic wiring upgrade.
     
  8. esgordon123

    esgordon123 New Member

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    I understand this. I was going off the thread title. That is the only thing I was going by. I'm sorry you misunderstand where I was coming from. I have answered the op. Yes I turn off at gas pumps. If you don't great if you do great to each his own.


    Sent from my iPhone using Tapatalk
     
  9. lifespeed

    lifespeed Member

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    It can be done either way, two circuits or a single large circuit. Total wire cross section and length determines the voltage drop. I have noticed the 7-pin gets warm when I run 30A through it, so I suspect it is responsible for considerable voltage drop. At some point I will have to implement an Anderson Powerpole to carry current, bypassing the 7-pin. But I am able to get away with this because my charger boosts the voltage to make up for the drop.
     
  10. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    I ran in the TV, 2- #12 wires because I had some auto grade #12 laying around. I twisted the end together and tinted them and than crimped to the connectors. On the ground side I ran redundent grounds , one to a bolt on the frame and another to the ground nut the the auto manufacture uses for the rear lights of the TV which is inside.

    On my current camper the converter is the rear of the camper and the battery charge wire runs to the converter using #10. About 25 feet. Than there is a #12 that runs foward about 10 feet to the fridge and there is a #10 that runs to the battery on the tongue about 20 feet. So on this camper to charge the battery it go's through about 45 feet of #10 and the fridge it go's throught 25 feet #10 and 10 feet #12.

    I do have issue charging the battey and running the fridge. So I do run the propane fridge. I know much debate? many people don't think it is safe to run with propane. But for 30-40 years the RV industry did not have a 12V option and everyone ran with propane.

    I could re-wire the camper, maybe run 2 lines from the TV battery? Or buy a 12v to 12V battery charger with a regulated output voltage and place it back in the camper. But after 25+ years of running the propane fridge when traveling. It is just to hard to get this old dog to use the new trick of the 12v fridge and spend all that time and money to make the mod to make it work right. But on warm/hot days I do turn off the propane fridge when fuleing.
     
  11. lifespeed

    lifespeed Member

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    A wiring upgrade would be adequate and doesn't cost much. The DC-input charger is much more expensive of course, but makes your TV a true battery charger.

    I think 98% of the campers and TVs out there are inadequately wired, hence all the complaints about 12V/batteries/charging etc. not working right.
     
  12. Keith Hawkins

    Keith Hawkins Active Member

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    I do not travel with mine running but if I were to run it I would 100% stop and turn it off prior to pulling into a gas station. I work for an oil company and have seen some pretty nasty things on what can happen from open flame, cigarettes ect being used while fuel is being pumped. Nope, would not want to risk my and my families life over keeping some milk cooled.
     
  13. kitphantom

    kitphantom Well-Known Member

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    @Canon 101
    That's what we do, seemed the logical way to handle it. Makes for some interesting stops. On gas is our only option on the road. Yesterday, we ended up not turning it back on after for quite a while, due to lack of trailer friendly gas stations. ( we were able to park at one to turn it off, then couldn't get near the pumps. Filled at another, no place to turn it on) temp rose to mid-40s, so stayed safe and freezer stayed. Old enough too.
    We're enjoying having the 'fridge, beginning to have a good handle on dealing with it on the road. Only 7 hours yesterday, still too long to leave it off.
     
  14. nineoaks2004

    nineoaks2004 Every meal is a picnic and every Day is a holiday

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    I never use LP on the road, I have seen a few explosions and fires in my travels
     

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