Sabatical said:
This thread now has me thinking I should cut the ciggy plug off and hook the leads to my 12v terminal block.
Cutting the then 12v cord is wise.
My friend's ARB fridge I had for 3 weeks had significant voltage drop on the provided 16 awg cord, and basically the low voltage cut out which was set for 10.1 volts, would activate when the battery voltage was 12.1 volts, so there was nearly 2 volts drop between battery and the input plug on the fridge.
Ciggy plugs make for horrible connectors. Their contacts are spring steel, not copper or even aluminum which are much better conductors than steel. The ciggy plug receptacles wires stock in vehicles can be horribly underwired, with too many connections between battery and fuseblock and fuse block and receptacle itself. And yes I know there are those with false yet ultimate confidence in their vehicles stock wiring. I know some 12v power ports in more modern vehicles will say 120 watts maximum, and these 12v compressor fridges max out at about 65 watts so it should be fine right? It is NOT.
If someone is using the stock ciggy plug cord, into a stock 12v receptacle, and the fridge does not work properly, or it stops working overnight because of the low voltage disconnect, then cut the cord.
Danfoss/Secop recommends their compressors are hooked directly to battery terminals and fused at the battery, that they not share a Buss with other devices. They also list a minimum wire gauge for certain lengths between fridge and battery, and these recommendations are for way way thicker copper than the cheesy horrible ciggy plugs that come with these portable units.
@ 12 volts they do not even list anything thinner than 12awg! Go over 8 feet in length and this goes to 10awg minimum.
Stock vehicle power ports likely have about 10 feet of 16 awg between fuse block and ciggy plug. Include the voltage drop from the ciggy receptacle and plug and the long cheesy length of 16awg wire from plug to fridge and the fridge not working properly simply should not be a surprise.
Here we have the compressor manufacturer saying specifically that the unit must be wired with thick copper, and yet most portable units which come with ciggy plug cords come with 16awg wire or thinner, and the cheapest plug design that they could buy in bulk. A plug that in the best scenario can only pass 60 watts and briefly before heating up excessively. If the plug/receptacle interface were the only bottleneck voltage drop might not be an issue, but then there is too thin of copper on either side of this connector. combine both of these voltage dropping sources and the compressor controller is not getting the voltage it needs to start the compressor.
http://www.ra.danfoss.com/Technical...nit_101n0600_12-24vdc_08-2011_dehc100m602.pdf
These portable fridge units need to be sold with the horrible Ciggy plug connections. They would lose half or 3/4 of their sales if the consumer was told they had to wire it directly to the battery, that it was not plug and play.
Not all fridges come with Danfoss/secop compressors, but all compressors are subject to the same issue of voltage drop on their power cords.
Those who wire up their own quality Ciggy plug receptacles with short lengths of 10 or 12 awg likely would not have issues with the low voltage cutout kicking in, or the compressor not starting. Those depending on the stock 12v outlets likely will have issues and the unit only works properly when battery voltage is 12.6v or higher.
All connectors wear out with use, and wear out faster with accumulated cycles. Ciggy plugs are simply horrible in this regard.
Stop wasting your battery power heating up a ciggy plug and receptacle and the surrounding copper. Cut the cord. If a connector is still required, 30 amp Anderson Powerpoles are very easy to install. One can put one of these on the original cord and then still be able to use the fridge on a ciggy plug, but when the fridge does not need to be portable, or used in other vehicles, then one can bypass the horrible wasteful intermittent connector which is a ciggy plug/ standard 12v power port plug and receptacle.
It is absolutely no surprise these 12v compressor fridges do not work properly when battery voltage drops to 12.6v or less, when the provided ciggy plug is providing power to the unit.
Cut the convenient cord.
If one insists on using the ciggy plug and receptacle, wire the receptacle with 10awg directly to fuse block. One can also run 10 or 12 awg right to the contacts in the plug itself, if they know how to solder. This will be a vast improvement, but the steel contacts will still cause some voltage drop and waste battery power as heat.
http://www.powerwerx.com/anderson-powerpoles/powerpole-sets/
30 amp powerpoles are very easy to crimp and assemble. The 45's are more involved.
