Solar DC power for refrigerator

[geO]

Does anyone use the DC setting for the refrigerator while boondocking?  I understand the 17-18amp draw on the batteries but the Zamp system can keep up with the demand on a bright sunny day. Doing a test now and so far impressed.

[topgun2]

The fridge is much more efficient on propane as opposed to either AC or DC.  Like you, I tried it once on DC just to see what would happen.  Unfortunately, I got a bit busy doing other "stuff" (like fishing) and forgot that I still had it on DC.  Thankfully I caught it in time before the batteries were totally depleted (50% lead acid), but, other than using it on DC for places where the use of propane is prohibited or perhaps while driving if one is opposed to using propane while going down the road, what's the use?

 

Bill

[geO]

The Zamp system is a work horse and my test has been going on for 4 hours and my batteries are 100% fully charged. This image shows total amp hours used and the zamp controller showing amps coming in. Notice the blue light on the controller is off because the batteries are 100%.

[geO]

Stopped my test at 1800 and my batteries pretty much stayed 100% throughout the day. I'm impressed with the system and getting a better handle on battery management is in the near future!

[ScubaRx]

Impressive results.  I've always run ours on Propane.

[Try2Relax]

Just to clarify, I do not have the Zamp system and I have a DC compressor fridge, so my questions are just out of curiosity.

 

If your display shows power usage, how much did you find that a day of fridge use consumed? What were the environmental conditions during your test, outside inside temps, I take it you just switched an already chilled fridge to DC only?

 

It is definitely interesting, as the amount of power required for DC to generate to the heat needed to run the ammonia process should be fairly sizable.

 

So, if nothing is running, what do you find the max output of the Zamp system to be?

 

Thanks

 

Edit: Just came across this

 

[Mike and Carol]

Impressive results. I’ve always run ours on Propane.

We use propane, too.

[Hikegsm]

We use DC when driving but otherwise always propane.  Good to know the Zamp solar can handle the load for a few hours if I forget to switch over ?.

[topgun2]

Yvonne & Doug -

 

I assume that you use some method of reminding yourselves that you are on DC for the fridge.  The cost of forgetting can be fairly expensive let alone maddening - the food in the fridge plus the batteries plus inconvenience.

 

Bill

[geO]

Just to clarify, I do not have the Zamp system and I have a DC compressor fridge, so my questions are just out of curiosity.

 

If your display shows power usage, how much did you find that a day of fridge use consumed? What were the environmental conditions during your test, outside inside temps, I take it you just switched an already chilled fridge to DC only?

 

It is definitely interesting, as the amount of power required for DC to generate to the heat needed to run the ammonia process should be fairly sizable.

 

So, if nothing is running, what do you find the max output of the Zamp system to be?

 

Thanks

 

 

 

 

 

The power usage was only .01 amp for the entire test. The zamp system seems to adjust amps in according to need. Once I turned the fridge off dc the charge controller dropped from 16 amps to about 2amp. Conditions were under pure sunny skies with out door temp in the mid 70's. Battery temp was 22c.  The fridge was chilled prior to testing and set on cool setting 3. According to the charge controller the system brought in 69.3 amps during test. Hope this helps and thanks for the link you posted.

[geO]

I would highly recommend folks that like boondocking to invest in a battery monitoring system. It truly is like a fuel gauge for the batteries!

[topgun2]

Mark -

 

You might already know this but ....    The current fridge in the Oliver has an "automatic" setting.  When using this setting it will default to 120v and then to propane if no 120v.  AS soon as 120v is available again it will automatically switch back.  In order to get to 12v you must move the switch to that setting and once placed there it will stay on 12v until you move the switch back to "automatic" or to "propane".

 

Bill

[Rumline]

I'd want to add the battery state of charge into the logic.  If you can intercept the wires from the fridge control panel this should be doable.  Get an Arduino and program it to prefer 120V, then 12V > 80% SOC, then propane.

 

Sure no problem!  Just add it to the list.....................