Everchill 12v battery drain test

[TC of NC]

We recently bought a Forest River Vibe 26RK and it came with the Everchill 12v fridge. When ordered I requested a second battery at the time I didn't know better to ask for better batteries but this is what we have (see picture). We have two of these 12 volt Diehard 24DC-1 dual purpose batteries. I just installed a battery monitor, I wanted to mount the display inside the trailer but I could not figure out how to run the wires inside where I would want to mount it so I mounted it on the A-frame near the batteries (see picture). I have it inside a waterproof container with a clear viewing window with a removable top.

The Test

I charged the batteries overnight to a full charge. The fridge is empty but already chilled on the middle temperature setting. Trailer is unplugged from external power for the test.

At 0830 this morning I started the test. I will check the battery voltage again at 2030 this evening.

With nothing running in the trailer it pulls .3 amps. After turning on the fridge it starts pulling 10 amps with compressor running and .3 amps when compressor cycles off. From this point the amp draw while compressor is running gradually drops. By 1030, after two hours under test the fridge is only pulling 5.5 amps while compressor is running and .3 amps when it cycles off.

I will report back at conclusion of the test.

[CivEngPE]

This is the thread I have been waiting for!

Do you have any solar as well?

[TitanMike]

I would also check and log the battery voltage along with amperage rather than just an end voltage.

[TC of NC]

Originally Posted by CivEngPE

This is the thread I have been waiting for!

Do you have any solar as well?

I do have a 165 watt solar panel that came pre-installed from the factory but the trailer is parked under an overhang so it won't produce anything during this test.

[TC of NC]

Originally Posted by TitanMike

I would also check and log the battery voltage along with amperage rather than just an end voltage.

Mike,

I am new to all this so I am not sure I understand your question regarding amperage. The battery will monitor voltage and amp draw. It also will give you a percentage of battery life left on the batteries but thus far I have been unable to get that function to work as I need to input the amp hr rating of the batteries and I don't know that.

[chriscowles]

Aili battery monitor manual:

https://diysolarforum.com/resources/...tor-manual.58/

Edit: yours may not be labeled Aili (mine was sold as QWork) but they're all the same.

[TitanMike]

Originally Posted by TC of NC

Mike,

I am new to all this so I am not sure I understand your question regarding amperage. The battery will monitor voltage and amp draw. It also will give you a percentage of battery life left on the batteries but thus far I have been unable to get that function to work as I need to input the amp hr rating of the batteries and I don't know that.

From the pictures I see you have Die Hard Silver Grp 24 batteries. They're advertised as having 110 minute Reserve Capacity which is determined by applying a 25 amp load and seeing how long it takes to run battery down to 10.5 volts. Not an exact conversion but at that rate the battery is only capable of delivering an estimated 71 amp hours. In general Group 24 batteries are considered 80 amp hour batteries (and group 27 more like 100 ah). This varies by manufacturer and "in the field" it can be even more if amp draw is lower.

Also bear in mind that if you want your batteries to last any length of time between the two batteries you only have a total of 70-80 amp hours.

You can set the battery monitor for the 70-80 amp hour capacity so it reads 0 SOC when you reach the desired max discharge level or set it for 140-160 ah and then recharge when you see 50% SOC.

And to add, since you have a "Battery Dependent" refrigerator I'd make plans for a battery upgrade in the near future if you plan on any extended "off grid" stays and don't want to rely on a generator or larger Solar array.

[TC of NC]

Mike, thanks for your contributions it helps me a lot. I do plan on getting some GC 130-140ah batteries in the near future. Don't currently have plans for long term boon docking but in the future I may.

1330 five hours into the test voltage reads 12.73 volts

This test will end at 2030 as stated above and I believe it will still have more than 50% capacity left but it will give me an idea. We are leaving tomorrow morning for our trip to California, Utah, Arizona etc. so nor more time for additional testing until we get back. When we get back home I will do some more testing.

[TitanMike]

Originally Posted by TC of NC

Mike, thanks for your contributions it helps me a lot. I do plan on getting some GC 130-140ah batteries in the near future. Don't currently have plans for long term boon docking but in the future I may.

Just remember that GC (golf cart) batteries most commonly used are 6 volt batteries. To get 12 volts they need to be wired in series.

With the size(s) you mentioned you won' be increasing the ah capacity above what you have as wiring batteries in series only doubles voltage. Capacity remains the same.

Now if you are referring to 12v GC batteries, although I'm unsure they come in that size and will fit where your current batteries are, that would be a game changer.

Most common two 12v battery setups use group 27 or group 31 batteries yielding 100-120+ ah ratings each (200-240+ ah in parallel.

Two 6v GC-2 batteries are ~225 ah wired in series.

Just a heads up.

[GarrettVibe]

I have the same camper, I installed two 6volt golf batteries, purchased from Sams Club. Rated at 230 amps, weigh about 65lbs a piece. I purchased two golf cart battery plastic boxes from a Golf Cart battery supply house. Fits perfect in the frame with about an inch left over each side. Had to cut off the handles on a band saw on the lids and boxes where the two come together or meet in the center. I mounted the monitor beside the bed in the corner on the night stand. Had to add 13ft of cable, directed it through the storage dept. down the front of the camper storage area, drilled a hole though the floor and fed it along the frame with the other existing cables to the battery.

Camped for a week Boondocking at Big Meadows Fed Park Skyline Drive, VA. With heat running all night and the frig also, some minimal use of lights. Each morning the batteries would read at about 75%. Used our small quiet generator during the allowed running times to bring them back up to 100% each evening. Very happy with the outcome.

[TC of NC]

Test Complete

2230 14 hours under test. Voltage 12.47 volts. When we get home from our trip I will do some more testing.

[PDuB-IA2MI]

Originally Posted by TC of NC

Test Complete

2230 14 hours under test. Voltage 12.47 volts. When we get home from our trip I will do some more testing.

Great work!

For reference, what was your volts at "full charge"? 13.1? 12.9? Thanks!

[TC of NC]

After I removed the battery from the charger it was more than 13 volts but it was slowly dropping I suppose at some point it would stabilize but I didn't wait long enough for it to stabilize. I put it under test after a minute or so after removing it from the charger.

[TC of NC]

Originally Posted by GarrettVibe

I have the same camper, I installed two 6volt golf batteries, purchased from Sams Club. Rated at 230 amps, weigh about 65lbs a piece. I purchased two golf cart battery plastic boxes from a Golf Cart battery supply house. Fits perfect in the frame with about an inch left over each side. Had to cut off the handles on a band saw on the lids and boxes where the two come together or meet in the center. I mounted the monitor beside the bed in the corner on the night stand. Had to add 13ft of cable, directed it through the storage dept. down the front of the camper storage area, drilled a hole though the floor and fed it along the frame with the other existing cables to the battery.

Camped for a week Boondocking at Big Meadows Fed Park Skyline Drive, VA. With heat running all night and the frig also, some minimal use of lights. Each morning the batteries would read at about 75%. Used our small quiet generator during the allowed running times to bring them back up to 100% each evening. Very happy with the outcome.

Garrett
How do you like your Vibe we love ours. Nice install job on the battery monitor. Would you mind taking some pictures of the wire routing for the display showing where you ran through and where you drilled access holes? What generator are you running and how long did it take the generator to charge the batteries up? Thanks.

[GarrettVibe]

We ordered our 26RK just before Covid shutdown, and then had to wait for things to open back up to get it in May. We really like it, it is our 3rd camper and I’m getting close to retirement so the reason for the couples camper. Our previous was a bunkhouse.

I can’t show you any pictures now of the wiring track, our camper is in storage as we are waiting for our Steel carport building to be completed and then the 26RK will be covered. The concrete is being poured this week. I’ll return to this thread once we have the camper back at home and I can get some pictures for you.

I wanted to mount the gauge at the panel by the bathroom but the wiring would have been in my opinion a nightmare. Then I thought about in a cabinet near the frig, so that I could trace the wiring through the outdoor frig compartment and then under to the front. So it just came back to mounting it near the bed, so that I can just look down on it during the night and see where we stand for power, since we usually boondock one week a year in the fall for the leaf changing season. The two 6 volt batteries with 230 amp hrs, out performed the factory 120amp marine battery by a long shot.

The hole drilled for the gauge is just about centered in the middle of the storage compartment. I had to measure out away from the wall to miss metal framing. I cut the 6’ wire feed in two pieces and then soldered in about another 6’ piece so that I could be at around 13ft which is about a foot more than I needed. I used Heat Shrink over the solder joints. Then I put the wire inside of 1/2” black corrugated wire chase. Ran the chase across the top of the underside of the storage compartment to the front then down in the corner. Drilled a 1/2” hole through. Was kind of scared about doing that, but it is about an inch thick there and mostly through styrofoam. I couldn’t drill through completely in the corner because of steal framework, so I drilled from below up into the storage, ends up being about 4” from the front and 2” from the side, but isn’t in the way for any storage stuff. Once underneath I wire tied it to existing trailer light wiring and then to the gas line and around inside of the tongue framework up to the battery. It looks very professional, and it does not look sloppy.

And I did some research on the Ryobi 2300 gen with the pull out handle and wheels. It received great reviews. It also connects to your phone so you can see power use, fuel capacity, and turn it off from your phone at night without having to go to the gen. It is half the cost of the Honda, and many people feel it is better. Our friends camp with us and have the Honda, our Ryobi was noticeably quieter and appeared to get better fuel hours over our friend‘s Honda. So I’m pleased with that purchase too.

[TitanMike]

Originally Posted by TC of NC

After I removed the battery from the charger it was more than 13 volts but it was slowly dropping I suppose at some point it would stabilize but I didn't wait long enough for it to stabilize. I put it under test after a minute or so after removing it from the charger.

That might skew the results somewhat but I'd guess not more than 1 or 2 %.

Surface charge goes away quick and doesn't really represent much stored energy.

[TC of NC]

Our first stop last night was in Tennessee. We parked about 8:00PM I disconnected the plug from the truck and turned the heater and ran it all night. By 8:00AM the battery was at 11.7 volts. Back o. The road again for Arizona. Now I know i need more battery. Garrett has the same camper but he did much better running the fridge and heater because he upgraded to two golf cart 6 v batteries.

[chriscowles]

Originally Posted by TC of NC

... Now I know i need more battery. Garrett has the same camper but he did much better running the fridge and heater because he upgraded to two golf cart 6 v batteries.

If you're thinking of getting the same flooded lead-acid battery array, consider this comparison of cost per Ah consumed over the life of the batteries with a 50% DOD.

Sam's Club Duracell GC2 (Deka GC10) 6V 215 Ah @ $89 (x2)
Expected cycle life @ 50%: 300 cycles. (Deka Flooded MonoBloc Data Sheet)
$89 x 2 / 300 x 215 x 50% = $178/32,250 = $0.0055/Ah

Trojan T-105 6V 225 Ah @ $159 (x2) (@ USABatterySales.com - not an endorsement)
Expected cycle life @ 50%: 1600 cycles (Trojan T-105 Data Sheet)
$159 x 2 / 1600 x 225 x 50% = $318/180,000 = $0.0017/Ah

In short, Trojan T-105s cost ~80% more than Sam's Club Duracell GC2s at initial purchase but cost about 1/3 as much per Ah over their useful life.

[CivEngPE]

Originally Posted by chriscowles

If you're thinking of getting the same flooded lead-acid battery array, consider this comparison of cost per Ah consumed over the life of the batteries with a 50% DOD.

Sam's Club Duracell GC2 (Deka GC10) 6V 215 Ah @ $89 (x2)
Expected cycle life @ 50%: 300 cycles. (Deka Flooded MonoBloc Data Sheet)
$89 x 2 / 300 x 215 x 50% = $178/32,250 = $0.0055/Ah

Trojan T-105 6V 225 Ah @ $159 (x2) (@ USABatterySales.com - not an endorsement)
Expected cycle life @ 50%: 1600 cycles (Trojan T-105 Data Sheet)
$159 x 2 / 1600 x 225 x 50% = $318/180,000 = $0.0017/Ah

In short, Trojan T-105s cost ~80% more than Sam's Club Duracell GC2s at initial purchase but cost about 1/3 as much per Ah over their useful life.

Or these: https://lithiummarinebattery.com/sho...4-128v-nominal

$1,395 X 1 / (5000 X 200 X 100%) = $.0014/AH And you get twice the useable capacity.

Or These:https://lithiummarinebattery.com/sho...4-128v-nominal

$600 X 1 / (5000 X 105 X 100%) = $.0011/AH For the same useable capacity.

[TC of NC]

We just stopped for the night in a truck rest area. No facilities just a place to park for the night. Battery is 12.86 volts at 1730. A lot warmer here than Tennessee so maybe we won't even need to run the heater. I'll report on battery status in the morning.