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Jacket
05-16-2011, 09:40 AM
Several times over the last couple of years I've had issues with my ARB fridge "shutting down" when the truck is parked. It throws an error code, which I've diagnosed as an auto shut-off feature on the fridge when the battery dips below a certain voltage level. The shut down threshold has 3 settings, and I have mine set at the lowest level (since I have an aux battery), which is around 10.5 volts. Fortunately, it runs fine when I'm driving, and the fridge seals well enough where I haven't had issues keeping my beer cold.

The battery threw the error again a couple days after I got back from Moab, so I did some testing.

- 12.04 volts at the battery.
- 12.04 volts at the 12 volt socket on the back of the 80.

but the fridge thinks it's much lower when the compressor cycles on. :(

My next theory is that the voltage is good at steady state, but when the load from the fridge cycles on, there is a drop that causes the system to shut back down. What is the best way to test this? And what might cause this behavior? My guesses are:

- insufficient wiring from fuse block to outlet (I've got around 6' of 18g wire).
- inadequate wiring in power socket (I've got a marine locking socket)
- battery is dying (no evidence of this)

Toss out any ideas you have. :cheers:

rover67
05-16-2011, 09:45 AM
The 12v plug that the fridge itself uses might just suck. On my edgestar, it used to shut down because of low voltage occasionally untill i zip tied the plug into the socket really tight. I think a proper solution would be to use a more secure plug and socket for the fridges. I think they draw enough to heat up the cheap 12v plugs since the plugs themselves are lossy.

My 12v outlets have like 4 ga wire going to them in the back and it still did what you are describing until I zip tied that plug tight.

Jacket
05-16-2011, 10:01 AM
Funny you say that - I've been through about 3 sets of plugs/sockets trying to find one that would actually lock and hold tight. This last combination seems to be the best I have, yet it's still not quite right.

ARB offers a wiring loom kit with 12v locking socket, so I may give it a shot.

nakman
05-16-2011, 10:03 AM
I agree on the 12v plug.. is the plug hot at all when you remove it from the socket? At the height of my Edgestar days, I could burn my thumb on the plug.. I ended up using a trailer wire harness and connection instead, with much better success and no appreciable heat loss- just one step away from hard wiring the thing.

The plug on my Engel is of much better quality though, and I'd presume your ARB would be similar.

Jacket
05-16-2011, 10:07 AM
It was a good quality plug, but it wouldn't hold tight in the socket so I replaced it with what I thought was a high quality marine plug and socket.

rover67
05-16-2011, 10:11 AM
post up a pic/link of the socket you used. I need to upgrade mine....

Is the new one hot after the fridge runs for a while? You could wire the volt meter at the fridge and watch what it does as the fridge cycles.. I have used sewing needles to pierce the insulation and get to the wires inside before, then you touch the voltmeter to the exposed needles. Just don't let them touch!

Red_Chili
05-16-2011, 10:45 AM
18 GA. might be a tad light too.

sleeoffroad
05-16-2011, 10:52 AM
ARB has a device that is supposed to be able to simulate the load and test the socket. I think the bottom line is the ARB fridge has a high start up current requirement and a lot of wiring / sockets does not like that. I would go away from the 12 v plug and use an mini Andersen plug

http://order.waytekwire.com/IMAGES/M37/items/37702FL.GIF

Jacket
05-16-2011, 12:12 PM
Thanks for the tip. Googling anderson plugs takes you to a number of Aussie forums where these plugs seem to be commonplace in truck and trailer apps.

treerootCO
05-16-2011, 12:53 PM
I am hoping these are a better fit than the marine ones.

Stolen from this thread (http://forum.ih8mud.com/80-series-tech/407097-ideas-adding-auxillary-12v-dc-115v-ac-outlets.html)

12v outlets with cover from a 2006 Sequoia
Part # 85530-34010
Part # 85535-0C020-E1

23708

23709

Red_Chili
05-16-2011, 01:21 PM
What is the inrush (startup) current for these fridges? That wiring looks ultra light duty!

60wag
05-16-2011, 01:25 PM
I had a portable coffee maker that the plug would get hotter than the water it was supposed to heat. It wasn't worth fixing so it got pitched. If anyone wants to pitch their fridge, let me know :)

Jacket
05-16-2011, 03:27 PM
post up a pic/link of the socket you used. I need to upgrade mine....

Is the new one hot after the fridge runs for a while? You could wire the volt meter at the fridge and watch what it does as the fridge cycles.. I have used sewing needles to pierce the insulation and get to the wires inside before, then you touch the voltmeter to the exposed needles. Just don't let them touch!

This is what I have:

http://www.marinco.com/product/12v-plug-receptacle

The locking part has been solid. I've never had the plug wiggle loose, which has been an ongoing problem with both this truck and my last one.
I don't see an amperage rating on the site, but I thought it was 10 amps.

DaveInDenver
05-16-2011, 04:12 PM
ARB has a device that is supposed to be able to simulate the load and test the socket. I think the bottom line is the ARB fridge has a high start up current requirement and a lot of wiring / sockets does not like that. I would go away from the 12 v plug and use an mini Andersen plug

http://order.waytekwire.com/IMAGES/M37/items/37702FL.GIF
Those might be overkill, but like the idea. I've wired a pigtail using 45 amp Andersen Powerpoles (Series PP) so that I can run my Engel from a ham station supply. I've converted most everything to Powerpoles and the 15, 30 and 45 amp ones are all compatible with each other. They have 75, 120 and 180 amp ones, but they are all physically larger and aren't directly compatible with the smaller ones. The ones you link are also made my Andersen, but are called the Series SB. The reason I went with the PP models is they are VERY common and usually standard with hams, ARES, RACES and many commercial radio and EMCOMM organizations. So finding a ~13.8V battery-, genset- or mains-based supply with them is not a problem.

http://www.powerwerx.com/_images/products/WP45_lrg.jpg

http://www.andersonpower.com/
http://www.powerwerx.com/
http://www.qsradio.com/

Lose the cigarette outlet, put one of these in its place.

http://www.powerwerx.com/_images/products/SplashBoot2_xlrg.jpg

DaveInDenver
05-16-2011, 04:32 PM
What is the inrush (startup) current for these fridges? That wiring looks ultra light duty!
My Engel MT45 inrush isn't huge (~5A), but it's also not nearly as smart with the under voltage protection. I have a 12AWG running about 12 feet from the battery to my outlet. Lowest I ever ran it was 2 days in the summer without starting the truck. The battery was at 11.7V (measured by my ham radio, so very unscientific). The fridge was still running and cold, although the engine cranked s-l-o-w.

FWIW, 18AWG wire is 6.5 milliohms per foot, so 6 feet is around 40 milliohms. If the fridge is 10A inrush, that's 0.4V of drop. I can't disagree that 18AWG is maybe light. Going to 12AWG or 14AWG would help, yielding V drops of about 0.10V and 0.15V respectively (assuming 10A inrush). I'd be surprised if the inrush is that high, but maybe it is and the UVL is just that sensitive. Suppose your battery is brand new and at 60% SOC, so sitting at about 12.2V and it's hit with a start-up, dropping to 11.8V. I dunno, seems sorta high still.

Jacket
05-17-2011, 08:43 AM
Thanks for the links Dave. I ordered some of those powerpoles last night - hopefully they'll do the trick.

DaveInDenver
05-17-2011, 09:01 AM
Thanks for the links Dave. I ordered some of those powerpoles last night - hopefully they'll do the trick.
In a pinch, HRO also has bags of the 15, 30 and 45 pieces.

Jacket
05-21-2011, 03:55 PM
Pretty solid stuff - almost like playing with legos. The little contacts are tricky to get into the housings after you crimp them, but otherwise it was easy to migrate from the 12v socket.

http://www.risingsun4x4club.org/uploads/Jacket/fzj80/anderson/anderson1.JPG

http://www.risingsun4x4club.org/uploads/Jacket/fzj80/anderson/anderson2.JPG

http://www.risingsun4x4club.org/uploads/Jacket/fzj80/anderson/anderson3.JPG

Crash
05-21-2011, 04:59 PM
Much smarter people than me have already commented here without saying anything about your battery voltages so maybe I'm out to lunch on this. I've recently read that a fully charged 12V battery should read somewhere around 12.9V and a battery reading 12.5V is considered at 50% of a full charge. A battery reading of 12.04V sounds like it is pretty weak and with a compressor kicking on, I can see it temporarily dropping to below the set shutoff point of the fridge.

Jacket
05-21-2011, 07:44 PM
It had been sitting for a couple days with the fridge on, so the battery wasn't at full charge. But you might be right; the battery is almost 4 years old now, and maybe it's lost some of it's ability. I'll be running it this week and then up to Paonia for the weekend, so I'll have a chance to see if the wiring and plugs make a difference.

Jacket
05-23-2011, 10:30 PM
The 80 has been sitting since Saturday with the fridge running, and I checked it tonight and it still seemed good. Voltage on the battery was 11.4V. I cranked the temperature down to 27* to get the compressor to cycle on, which it did and ran steadily and happily for 5 minutes.

So the problem definitely stems from something in the 12v socket plug setup I had previously. With 14g wire and the Anderson plugs the voltage drop seems to be minimal. :beer:

subzali
05-24-2011, 08:07 AM
Will your battery start the 80 on 11.4V?

Looks like a very cool solution!

DaveInDenver
05-24-2011, 08:32 AM
Not sure if it would work with your outlet, but you see the little hole in the middle of the assembled PowerPole? You are supposed to put a tiny roll pin in there to keep the two parts from sliding back.

http://home.comcast.net/~buck0/powerpole.gif

But if you leave out the roll pin you can thread a small ziptie or a twisted piece of wire through both holes of the mated connector, which keeps them from vibrating apart.

Jacket
05-24-2011, 09:04 AM
Will your battery start the 80 on 11.4V?

Looks like a very cool solution!

It's an aux battery, so it's not needed for starting.

Dave - The wall mount came with a roll pin, but the individual connectors I bought are actually bonded together and won't slide.

DaveInDenver
05-24-2011, 09:37 AM
It's an aux battery, so it's not needed for starting.

Dave - The wall mount came with a roll pin, but the individual connectors I bought are actually bonded together and won't slide.
Understand, a dab of super glue is good for that. I was thinking along the lines of the fridge plug vibrating out of the bulkhead.

Jacket
06-22-2011, 01:12 PM
Dave - were you thinking something like this:

http://www.powerwerx.com/_images/products/110G68_xlrg.jpg

These plugs don't really "lock" together, so I could see there being some risk of separation if excessive vibrations were present.

CardinalFJ60
12-03-2012, 11:25 AM
Hey Matt, I'm about to do this same thing to try to address that crazy RFI coming from my fridge (doing this before looking at grounding inside the fridge).

Questions...

1. did you just cut off the cig lighter end and PP the existing plug that goes to the fridge? Or did you make a whole new 10g jumper?
2. Do I need to figure out Pos/Neg on that existing plug? if so, how?

thanks!

Jacket
12-03-2012, 11:43 AM
I used the existing ARB plug and disassembled the 12v male socket plug end, and replaced it with the PP connectors. It's fairly obvious once you open up the socket which wire is which, but as I recall the positive wire runs to the metal tip at the end of the plug and the negative wire joins the side contacts that touch the outside circumference of the female socket.

Making this change is a good move. I fiddled with different 12v sockets and wires for for months trying to solve various problems before changing to the Powerpoles. I haven't given it a single thought since I made the change.

CardinalFJ60
12-03-2012, 11:55 AM
thanks!!!!

rover67
12-03-2012, 12:03 PM
I did my fridge with the power poles and it is great.

I replaced the whole wire coming from the board inside the fridge. Probably more than you need to do. Mine is the edgestar so it needed a bit more work. I think the majority of the edgestars complaints stem from the bad power cord and mine has worked perfectly ever since I did the conversion.