wiring res fridge

[Chopperbob]

Whats the best way to wire a res fridge? I have a 2000w
inverter, 4000w gen and shore power. ATS? Manual?
Thanks!
Bob

[time2roll]

15 amp plug and play (almost)

http://www.donrowe.com/KISAE-TS15A-Automatic-Transfer-Switch-p/ts15a.htm

[Chopperbob]

I am going to install a 30a ATS. Thanks everyone for all the thoughts.

[Gdetrailer]

MEXICOWANDERER wrote:
You'd think a DPDT relay is astrophysics or something. Incoming AC priority of course.

"Rocket science" to some folks I guess.

For me, I didn't want to waste a couple of extra watts of power that a relay would use.

But yes, a relay can be subbed in for the manual switch I used..

Unfortunately now days finding a store that you can walk into that has relays is a thing of the past for most people.. Used to be able to walk into a Radio Shack at get a DPDT relay with 10A contacts rated for 120V..

Now I have to order stuff like that off the wobbly web.

Not to mention I can envision a few self induced problems down the road with a relay that has no switch over time delay like a real ATS has..

In the whole realm of the world a purpose built ATS is not all that expensive considering it has delay protection built in which helps to minimize any damage due to rapid switchovers..

HERE is a 30A ATS for $53 which is cheap insurance and you get the best of both worlds..

I would rather not be so cheap to use a inverter to run the fridge when on shore power..

[MEXICOWANDERER]

You'd think a DPDT relay is astrophysics or something. Incoming AC priority of course.

[Gdetrailer]

csamayfield55 wrote:
You guys agree making this way too hard.

Plug it into the inverter behind the fridge. Leave it plugged into 12 volt power. It will power it directly off the batteries when no 120. When 120mis there your converter will power it indirectly through the action of charging the battery. No switches, no unplugging or replugging. It works just like the 12 volt lights in the trailer

Chris

Wrong.

Doesn't work that way.

Doing it your way will overwork the CONVERTER not to mention waste a lot of power when you do have 120V.

A home fridge will have a rather large start up surge, I measured that on mine. Mine has .9A (at 120V) run current but start up surge was 10A-11A at 120V. Translate that to 12V and you will have 9A-10A at 12V run current and 90A-100A at 12V.

This means just to cover your fridge you will need a converter of a MIN of 100A at 12V! YES, I realize the batteries will "buffer" the fridge load" but in reality a small converter (35A-80A) is not going to cut it.

Doing your way also will wear out the batteries much faster due to all the surges if you do not have a converter of sufficient size..

I personally don't care two bits if RV manufacturers are doing the way you have suggested.. It is a CHEAP way to do it and CHEAP often comes around an bits one in the rear..

ATS for automatic switch over is not all that expensive nor have possible bad side effects (such as forgetting to turn off the inverter when in storage)..

I made my own MANUAL switchover for my home fridge, it was simple and require only a handful of cheap parts which are easily sourced in Home Depot or Lowes.

I used a double pole toggle switch which has ON/OFF/ON, one plastic surface mount work box.

One blank cover for the switch box.

Two six foot power cords with plugs attached.

One short cord with a single outlet socket (think female end of a extension cord).

Wire the cord with female end to the center common terminals and the two power cords with plugs to the outside terminals.

Plug one male plug into the shore power and the other into the inverter.

Plug the fridge into the female end from the switch box.

Total cost, $15.

I mounted my box under the fridge.

Operation is simple, when plugged into the shore power I have the switch set to shore.

To change to inverter I move the switch to OFF, wait 5 minutes (allows time for the fridge to reset) then switch to the inverter.

Just reverse the order to go back to shore power.

When on shore power I simply turn the inverter off.

Running fridge from inverter even when on shore power really wastes a lot of energy due to the double conversion.. I am not about to pay double for my shore power..

[MEXICOWANDERER]

Absorbsion refrigerator, useful accessory...

[CA_Traveler]

Chopperbob,

And there you have it - for most campers the additional refer draw would discharge the batteries more for each day in the winter.

An energy audit might be in your future and that could lead to more batteries, more solar, gen, change of camping habits, etc. Or an absorption refer.

[Almot]

MrWizard wrote:
Some of these new fridges, have the coils, in the sides of the fridge , some in the back
Most are not exposed any more, so you have figure out where they are before you put foam anywhere

True.

Yes, 550W in the South in winter will harvest 80-90 AH on a good day. I'm getting 80 AH with 490W. With other items drawing 40-50 AH - not including MW and other high-wattage AC loads - it leaves nothing for 120V fridge.

[MrWizard]

Some of these new fridges, have the coils, in the sides of the fridge , some in the back
Most are not exposed any more, so you have figure out where they are before you put foam anywhere

[MEXICOWANDERER]

By FAR the most important thing you can do is clad the top, bottom and sides with 2" rigid foam. This alone will reduce energy consumption by a whole bunch. And it will keep the freezer colder and interior temperatures more even. The door poses a problem because of visual aesthetics. But remember, thermal is not like water, a small hole will not drain out the water. Reducing BTU loss (pass through) works. Period.

You can treat the rear behind the condenser coil with pressurized foam. It takes patience but the reward will be great.

EVERY refrigerator I own has it's own convection system which is similar to the access door and exhaust cap. A tiny muffin fan blowing across the refrigerant entry part of the condenser (Max Delta T) helps significantly. Use a MANUAL air conditioner dial thermostat control to determine when this fan runs. Place it as high up as possible very near to the condenser coil.

These modifications work and they work spectacularly. Expect a 30 - 50% reduction in energy use, if the rear is also insulated via foam.

How important is insulation?

Check out the performance of a YETI ice chest versus even the highest rated Coleman. Forget the price issue, focus on performance - you are making your own YETI.

Hope this helps

[CA_Traveler]

For mostly dry camping running the refer on the inverter only when plugged in makes sense to me. There are efficiency losses for both the charger and inverter that an ATS would eliminate.

[CA_Traveler]

Almot wrote:

CA Traveler wrote:
His 550W solar should keep the battery charged for most days.

Er... flat 550W? with MW and possibly other AC loads? Let's say "for most days in May through August in SoCal" :). In December it won't harvest enough for that fridge alone.

Try 100/12*8 hours = 67Ah. On 12/24/14 in Oceanside (S CA) I harvested 113Ah on 750W flat or 113*550/750 = 83Ah.

AC and clouds are a deal buster but otherwise he should be OK with the same conditions.

Additional loads, 50% refer cycle time, etc are of course factors.

[MrWizard]

Grid power direct
Or
Grid power thru inverter
Is still grid power
The difference is the converter works harder
When it is charging the batteries and powering the inverter

[wolfe10]

Chopperbob wrote:
Oh my inverter is 2000 psw.

Is it an inverter only or inverter/charger.

Does it have a built in ATS (pass through feature)?