hi delta18, & any other interested listeners, we had a problem with our fridge on 12 volt operation. it never really worked well from the start. it came to a head last week after traveling around narrabri, through to bourke, down the darling river run through louth, tilpa, wilcannia, & broken hill. after throwing out 3 lots of spoilt food we called an auto elec. in broken hill. he said that our problem was not uncommon, with many vans arriving in broken hill with similar. firstly, he found the fuse to the van had blown, he said the fuse was a 10 amp & with the fridge drawing a minimum of 8 amps it was working on max load when the fridge was on. he changed the fuse to 30 amp. he then said the pins on my 7 pin plug were not allowing sufficient charge to the van & changed this to a 12 (i think) pin plug, saying the pins themselves were twice the size, also by piggy backing pins to charge the van there would be more than enough charge getting back to the van. he then fitted a larger earth from the 12 pin plug. i had already fitted a 6 mil feed to the van & this did not have to be changed. well all's well that ends well, now sitting on the river bank at wentworth sipping a cold beer & a chardy. they can never be too cold. it was by far the best dollars we have spent as it has cleared, problem fixed, happy days. cheers chris & terry
Cruising Granny said
03:13 PM Nov 26, 2009
Good luck to you solving that problem.
Is the fridge a 3-way van fridge or something else?
I haven't had any probs with the one in my van, but it pays to be warned.
Disco Duck said
06:39 PM Nov 26, 2009
Good information....Chris and Terry...............Thanks for that!!
I love the wentworth Caravan Park ......................Top Spot.
Enjoy your stay and have one for us!!
jimricho said
07:17 PM Nov 26, 2009
The sparky in BH has put you on the right track by fixing up what reads like a previous bodgie job. The 12 pin connector is a better option than the 7 pin flat.
One thing to consider....does the "12 volt" supply to the fridge from the car "cut off" automatically when the engine isn't running? If not get your sparky to install a relay to do this otherwise you're setting yourself up for a flat (and possibly stuffed) battery.
An alternative to a relay is a device known as a "Fridge Switch" that's installed at the caravan end of the fridge circuit that detects movement or more correctly lack thereof and cuts off the fridge when the rig is stationary. I have no experience with this device so this is a suggestion rather than a recommendation.
BobnBev said
08:16 PM Nov 26, 2009
Hi Criss n terry. Thoes 3 way little thingys can be a big problem in the real hot weather... I fitted anderson plugs along side the standed 7 pin plug, to do the job of keeping the van batteries charged when driving.. 50amp andersons and good wire is the way to go.. your just over the river from us... nice there real nice....Bob
jimricho said
08:40 PM Nov 26, 2009
Anderson plugs are good option and enable the 7 pin connectors to be retained. I prefer the large round 7 pins to the flat 7 pins. This judgment is the result of experience with both types including boat trailers.
Be aware that Anderson connectors contain small steel retaining springs that can rust out (I've had it happen) and some steps should be taken to protect the connector from the elements. There are various boots and covers available for this.
Note also that the charging circuit as described above should be wired separately to the fridge circuit otherwise the fridge will discharge the van battery.
I still think your sparky's choice of a 12 pin was a good one
Jim
-- Edited by jimricho on Thursday 26th of November 2009 07:46:05 PM
justcruisin01 said
09:32 AM Nov 27, 2009
Iv'e just changed all mine over to thr 12 pin, duplicated the accessorysupply in the plug ,also the earth & electric brakes as the brake terminal was burning up .
This doubbles your chances ,although i was noy having any trouble with the fridge.
PeterD said
10:58 PM Nov 27, 2009
A couple of vans back I upgraded the fridge wire for correct operation on 12 V. The next thing that happened was pin 2 in the 7 pin plug welded itself into the socket. It took the park manager at Menindee and me nearly 15 minutes to break the two apart (and that left most of the pin in the socket.) The next modification was to install the 12 pin plug/socket. My following two vans have been the same.
The small pins are rated for around 5 - 7 A and the large ones 30 - 35 A Pin 8 goes to the battery booster and pin 9 goes to the fridge. I have a relay in the fridge line controlled by the run position on the ignition switch and the relay in the booster line controlled by the accessory circuit of the ignition switch. That way if I wish to give the van battery a boost I just switch to accessories and no power goes to the fridge.
jimricho said
07:17 PM Nov 28, 2009
Is there a wiring (pin-out) standard for the additional 35A pins in the 12 pin connector?
Disco Duck said
07:30 PM Nov 28, 2009
Try this link Jimricho........I don't know if this is what you are looking for?
-- Edited by Disco Duck on Saturday 28th of November 2009 06:36:07 PM
Disco Duck said
07:37 PM Nov 28, 2009
There is another good link here.
http://www.supertramp.com.au/forum/printer_friendly_posts.asp?TID=710
jimricho said
08:47 PM Nov 28, 2009
Thanks DD for that.
The first link covers the pinouts very clearly and is a worthwhile site for anyone wiring trailer connectors. The other sites have useful information too. I have bookmarked all three.
regards,
Jim
Delta18 said
10:50 PM Nov 28, 2009
All good info Chris and Terry. As we have solar on the van roof we have no connection from the car to the van for battery charging.
The 12v for the fridge when travelling is supplied from the car via a 30amp Andersen plug and dedicated heavy wiring.
I will have to check the integrity of this plug as has been mentioned, they can deteriorate.
I have plugged the van into 240v now at home to try it and it is working perfectly, froze 2 cups of water in 3 hours. The weather has been very mild though.
Cheers
jimricho said
05:26 PM Nov 29, 2009
You will need a voltmeter (or multimeter) to check this wiring with the van connected and the car's engine running, also of course the fridge turned on and on 12v. Check the voltage at the 12v input terminals on the back of the fridge. Should be accessible from outside the van by removing the bottom vent cover.
Keep the fridge's 12v wiring completely independent of the 12v "house" wiring including solar panels etc.
When not travelling use gas or 240v.
To test the fridge for cooling on 12v at home you will need a 240v to 12v DC power supply of at least 20 amp capacity to substitute for the battery. A "spare" battery connected to a 20 amp battery charger will also work.
rusty_12 said
12:36 PM Nov 30, 2009
Jim, if you change yuor plug to the 12pin flat, is it possible to still use the 7 pin flat that is on the box trailer or does one have to change all plugs?
jimricho said
05:08 PM Nov 30, 2009
rusty_12 wrote:
Jim, if you change yuor plug to the 12pin flat, is it possible to still use the 7 pin flat that is on the box trailer or does one have to change all plugs?
Hi Russell, welcome to the forum.
The short answer is I'm not sure.....
The 7 pin trailer plug may plug into the 12 pin vehicle socket as the first 7 pins are the same dimensions and connection pin-outs but the connector shells may not be compatible. Someone else may have a better idea on this. I very much doubt the 12 pin trailer plugs would fit the 7 pin vehicle sockets due to the extra pins.
I'm using large 7 pin round plugs as I too have a compatibility issue with a tent/box trailer and a boat trailer as well as my "wind-up" camper (caravan). To date I've been able to rely on "ground" power in caravan parks to recharge the van battery and I don't need a charging circuit from the car (as yet) so the 7 pin is adequate and the larger pins carry the fridge current ok
Be aware that Anderson connectors contain small steel retaining springs that can rust out (I've had it happen) and some steps should be taken to protect the connector from the elements. There are various boots and covers available for this.
Note also that the charging circuit as described above should be wired separately to the fridge circuit otherwise the fridge will discharge the van battery.
I still think your sparky's choice of a 12 pin was a good one
Jim
-- Edited by jimricho on Thursday 26th of November 2009 07:46:05 PM
This doubbles your chances ,although i was noy having any trouble with the fridge.
http://www.campertrailers.org/trailer_wiring_diagram.htm
http://myswag.org/forum/index.php?topic=4047.msg57165;topicseen
-- Edited by Disco Duck on Saturday 28th of November 2009 06:36:07 PM
The short answer is I'm not sure.....
The 7 pin trailer plug may plug into the 12 pin vehicle socket as the first 7 pins are the same dimensions and connection pin-outs but the connector shells may not be compatible. Someone else may have a better idea on this. I very much doubt the 12 pin trailer plugs would fit the 7 pin vehicle sockets due to the extra pins.
I'm using large 7 pin round plugs as I too have a compatibility issue with a tent/box trailer and a boat trailer as well as my "wind-up" camper (caravan). To date I've been able to rely on "ground" power in caravan parks to recharge the van battery and I don't need a charging circuit from the car (as yet) so the 7 pin is adequate and the larger pins carry the fridge current ok
Jim