Playing with New Fridges.

[Ridge Runner]

I'm designing for worst case scenario. Hot day and warm night. So if Hot n Sunny the fridge will run most of the day @ 3.0 Amps.

Overnight I think it might be around 50% run, so 1.5 AH. Daylight saving, say allow 12 hours night run for 15-20 Amps.

So if the 100W produces close to its rating, it will run the fridge and the surplus will replace the previous nights use.

That's assuming I'm not driving, in which case the DC-DC will do the job.

I've found winter time fridge power demand not worst case

The reason behind me going for so many Is because I have the 47L fridge and the 78L, So my plan is because a 100w will put out around 5 Amps in winter on a bad day with no sun, So if I use 20 to 30 Amps per day then I need between 4 and 6 panels depending on if they are 100s or 140s So even on bad days I will be just breaking even and Once the sky is clear then the rest is all Gravy, So I want a set up that will cover or is equal to the power I use. :Y:

J.

 

[condor22]

Way to go RR. It only goes to prove what I've said many times, "we all have different needs, equipment and budgets",. But follow the correct procedure and a setup will do what you want it to.

BTW - as I mentioned, I regularly use 30-35 AH in winter. That it is not fridge use doesn't matter, my 200W of panels will bring the battery back to 100% by mid afternoon, rain, hail or shine

 

[Ridge Runner]

Way to go RR. It only goes to prove what I've said many times, "we all have different needs, equipment and budgets",. But follow the correct procedure and a setup will do what you want it to.

BTW - as I mentioned, I regularly use 30-35 AH in winter. That it is not fridge use doesn't matter, my 200W of panels will bring the battery back to 100% by mid afternoon, rain, hail or shine

Many folks misjudge the power requirements Although they work out how much power they need Correctly they either use the panels full rating or use the 80% Rule But that only applies to spring and summer times, which leaves a lot to chance once winter sets in, So I decided to use the Winter rating to match my usage so no matter what happens any other time of the year I will always have power to spare.

I Bought a Victron 100/20 MTTP charge controller so it will hand up to 100v So 4 X 140w will give me 560w at about 28Ah in Winter and each panel can put out up to 98Amps per day in summer so that has the ability to put out 392Amps on a good day less 20% etc.

J.

 

[Ridge Runner]

Sorry Condor22.

I got my maths wrong a bit here Because I forgot to add the run time to the off time, the run time of 17mins is 0.2883 hours add that to the 1.366 = 1.6543 hours, So you divide the 1.1 Amps by 1.6543 Hours is Equal to 0.664 Amps Per Hour is the power Used.,

If you take that 1.1 Amps and divide it by 17mins = 0.064 Amps per minute, Multiply that by 60 minutes = 1 Hour then it would be using 3.882 Amps per hour as per the meter reading during it's run time but because it only ran for 17 minutes then the Ah used is a lot less.

 

[Nightjar]

Stepping back to LW #36. Blanking out the windows may keep prying eyes off your goodies, but they know they are there! As for keeping the vehicle cool has my doubts. If the vehicle is all locked up with windows closed the inside temperature will be the same with or without window blankets.
One of the main reasons for purchasing a portable panel was to allow the vehicle to be parked in shade with flaps and windows open. (When we are prospecting) and place the fold up in the sun away from vehicle. Taking into account where we go detecting we rarely see another person for weeks at a time so the open vehicle is safe from sticky fingers.
When the sun drops I wind the dials back a couple of degrees because the over night temps drop to about the fridge temp of 3C. When the 39L freezer is empty and shutdown I just set and forget the combo it chugs away merrily all day all night with of course shorter run times through the night.
When we head into town for supplies one of us always stays with vehicle.

RR & Condor, maths was my top subject at school however does it really help your panels and fridges knowing the fridge draws 3.382AH?
Each for their own of course, you enjoy the challenge so who am I to disagree. (Smiley things below don't work. hahahaahaahhaahah)

 

[Nightjar]

 

[Ridge Runner]

RR & Condor, maths was my top subject at school however does it really help your panels and fridges knowing the fridge draws 3.382AH?
Each for their own of course, you enjoy the challenge so who am I to disagree. (Smiley things below don't work. hahahaahaahhaahah)

I just want to know which fridge will give me the most usage from my power supply for my set up, Not only that since I have been playing around doing these different tests, My power bills are less than $150 per year which has freed up money to buy new toys with.

 

[ctxkid]

Stepping back to LW #36. Blanking out the windows may keep prying eyes off your goodies, but they know they are there! As for keeping the vehicle cool has my doubts. If the vehicle is all locked up with windows closed the inside temperature will be the same with or without window blankets.

i'll answer as well as hopefully LW will .........
what cannot be seen , does not trigger the i want it response ] we don't all live or use our vehicles as you :8 so power to you mate ower: :clap: erfect:
The shiny blanky's on the windows DOES make a difference erfect: :sunny: we have no reason to lie :Y: :fistpump: advise to you "try it" :awful:

 

[LONEWOLF]

x2 ctx, I have noticed a difference too.
When putting things in the rear, I noticed it was a bit hot, so after fitting them, it is definitely a lot cooler. I only have them fitted to the rear sides when driving around but have ones ready for when im parked up camping.... No issues with Blind spots... I use my Mirrors and know who is around me..

I don't have a fridge anymore , but can see the benefit if I did have one...
Cooler Ambient Temperatures make any sort of Refrigeration run more efficient...
I know cause I have installed Industrial/Commercial Air-con for over 40yrs....

Give it a go NJ, you might be surprised...

LW....

 

[AngerManagement]

Insulation helps and that means shade or sun screens/blocks BUT the screens only help short term. Without substantial insulation the temps internal to the car / canopy will rise over time.

While previously I have dome years of studies on Vaccine and Blood transport/management for WHO; I Have been doing lots of temperature studies with bee hives of recent times. AND as expected it all comes back to Thermal Mass / Surface Area and Air flow. Hence a big log or a hive in a solid wall of in the ground does much better than a thin walled man made box. And of course colour

Same for any cooling system - Needs a suitable environment good air flow to remove excess heat. In the car the best one can hope to do it to limit the extremes such that the fridge can get some down time.

There is no one solution suits all but what you can do is to minimize heat transfer via Conduction and Convection and limit those same losses in the fridge.

 

[condor22]

Simple solution for reducing vehicle temp -

We all move to Tassie

 

[AngerManagement]

Simple solution for reducing vehicle temp -

We all move to Tassie

Problem is I want a Fridge as well not just a freezer :lol:

 

[condor22]

Probably don't need a fridge down there most of the time anyway

 

[madtuna]

RR where are you mounting these 4 panels?

The solar I'm looking at mounting on my roof rack will either be an 80W or 100W. I'm going to mount it across the rear of the rack. The 80W sits inside the perimeter of the rack (sides) by about 15mm. I'd flush mount the edge of the panel with the rack at the back of the rack, but need angle brackets to bridge at the front. The 100W panel extends 37mm over the outer side edge of the roof rack, so it does not need bridging brackets. It would be fixed similar to the 80W at the rear, and need a small angle bracket at the front, or..... a bolt and locknut near the front through the panel frame and rack, depending on the panel frame configuration.

Pros n Cons - The 80W panel is only 25.4mm thick and weighs 5.4kg. The 100W panel is 35 thick and 7.7kg. So smaller is lighter, lower profile and within the rack envelope.

The deciding factor will, as it should be, the power output. The 80W = 3.85 Amps, the 100W = 5.72 Amps. (nominal)

As my Engel draws 3 amps when running the 80W will roughly keep up with it, but will probably not replace overnight use. As a simple guide, I believe that solar output Amps should be at least double load amps to do this. So a 160W panel would be better, but impractical as it is way to big for my setup. Given that the rack is high and the 100W panel is still well within vehicle width, this will be my choice. You'd need to be in excess of 7' tall to scone yourself

It will be a while before I do the job, but I'll post pics when I have.....

Well I found a Twin Axle Caravan I am thinking of buying So I can go detecting and Touring but I am also toying with the Idea of getting an RV/Camper so real estate up on the roof won't be a problem,

The bloke at the Solar Shop does most solar panels in two different sizes Some are square-ish some are broad and long and some are long and narrow So you can put narrow ones round the edge and Squarer ones across the ends and vice versa, If the space is really narrow then I would put 5 X 60w or 5 X 80w etc. Some times you just have to get IE one panel at 100w that measures 1190mm X 625mm and also buy another 100w panel that measures 900mm X 750mm or what ever the true sizes might be, Or a couple of 80w measuring 900 X 370mm Or 750mm X 550mm etc, as long as their wattage matches then all is well.

As for your Engel amps while running is not much at all, The ARB can draw a bit more than that but it can Run anywhere from 11 minutes up to 19 or 20 minutes "IF" you pack it Wrong and then it then shuts off for anything Up To and Over 2 hours, SO If it has run for 17 minutes It might of used a total of 1.1 Amps and then it might shut off for 1h 22m So that's 1.366 hours for a complete Duty Cycle, If you Take that 1.1 Amps Divide it by 1.366 hours equals 0.805Amps per hour,

Those are fairly normal every day type figures but in Temps of around 16*/17*c with it set to 4*c I have seen it use as little as 0.396 Ah +/-over a 23/24 hour period with a Total of 120w.

Now it is warmer I am running these tests on AC and DC and at 2*c and -12*c for bo the the ARB 47L and the Snomaster CL 35L, but the results so far are quite a shock,

Just buy an old Mr Whippy van and throw a roof top tent on the top. Probably work out cheaper than the cost of all your fridges and will hold a stack more beer :Y:

 

[Ridge Runner]

Insulation helps and that means shade or sun screens/blocks BUT the screens only help short term. Without substantial insulation the temps internal to the car / canopy will rise over time.

While previously I have dome years of studies on Vaccine and Blood transport/management for WHO; I Have been doing lots of temperature studies with bee hives of recent times. AND as expected it all comes back to Thermal Mass / Surface Area and Air flow. Hence a big log or a hive in a solid wall of in the ground does much better than a thin walled man made box. And of course colour

Same for any cooling system - Needs a suitable environment good air flow to remove excess heat. In the car the best one can hope to do it to limit the extremes such that the fridge can get some down time.

There is no one solution suits all but what you can do is to minimize heat transfer via Conduction and Convection and limit those same losses in the fridge.

Well done AM, just from your findings alone In that case can tell you that some 4x4 fridges are NOT a good Idea for in Australia, regardless of them having a good Rep.

 

[Nightjar]

When I purchased the 39L covers were not available. However running it at 3C was not a problem.
After the first trip, decided to get a cover made, not only to protect from scratches but improve insulation. Putting your hand on the outside metal case felt quite warm during the day.
Had a cover made out of canvas and had it lined with an old thick Onkaparinga woolen blanket.
The next time I ran the fridge without altering the dial, the portable thermometer inside the fridge read -1C.
On a recent trip, pulled out a pack of meat to thaw for nights meal and did not pull the lid top cover back into place.
As we drove to our days detecting spot we noticed the in cab wireless thermometer read out was reading -10C, up from the usual -13.
When we pulled up I checked and then realised the lid cover was not in place. Corrected that, when we returned to vehicle a couple of hours later, old yella was back down to -13.

 

[madtuna]

Hard to beat the old Engels, hard to kill.
This one bounced out of the back of the ute and went end over end about 5 or 6 time before a tree stopped it's progress.
A bit beat up but still works like a beauty! :Y:

I also have an old bright yellow Evacool fridgemate. These things are rated the number 1 fridge on the market for ugly.
They are also tough as nails, probably more so than the Engle. It also bounced out of the ute and still goes like the day it was bought. Haven't got a photo, didn't bother as there was no visible damage.

Both work well out here in high 40's heat, the Evacool slightly better than the Engel in my experience.

While it's probably handy to know, I don't bother with all that amps, watts and current draw stuff, it's too technical for my little brain. I just worked a more simpler calculation that even an idiot could understand....is my stuff cold and is the battery charged? If the answer is yes to both those questions then you've nailed it!

 

[Jaros]

A very well built unit. Metal ilo plastics. I'm keeping mine!!!!

 

[Ridge Runner]

I have the very early Waeco CF60 analogue fridge i bought new for $800. Crrappy lids etc but in the early days it was a bluddy efficient fridge. Over the years the thermistor was slowly crapping itself to the point its current draw was just way too much. I bought a digital controller off Ebay for $5, wired it up instead of the thermistor and wow what a difference! Minute adjustment instead of the too warm 3 lights or too cold 4 lights. I then replaced the .8A 100mm fan with two .08A 120mm fans, one pushing the other pulling. It is now a very efficient fridge with minimal draw.

I bought off Facebook marketplace an immaculate digital CF50 with cover with a faulty control board at the top of the fridge for $150. Same mods and its a bluddy ripper.

I bought a CF40 with the same problem as the last for $50 and fitted the same controller. This was going to travel in the back of the ute but its going to a friend who has given me help while i was getting over a broken foot.

Look, I understand these Waecos arent up there with the best but you can buy and mod them to be a very cheap and efficient fridge.

Dometic / Waeco are damn good fridges and Their association with ARB has added a lot of features to 4x4 fridges never seen before ,ARB got them to add these features because Dometic Waeco make the ARB fridges for ARB and they also make Elecrolux Fridges Too and then they started fitting some of those bits to their own CF/CFX fridges, Dometic /Waeco are true pioneers when it comes to building fridges.

 

[Ridge Runner]

Evercool make them kickass ones RR,well make is probably a loose term,heres one on there refurbished list
same as what we bought,no engel but going ok.....

https://www.evakool.com.au/89-litre-evakool-kickass-metal-fridge-freezer-factory-refurbished

Yeah, I got a photo of the kickass model and they use the smaller Danfos DB GH compressors which means they have fitted a 12v adapter internally, Some fridges have the 12v Adapter but you have to plug it in your selfeither way the compressors are good but it is how the different voltages are catered for is what is important.