ARB Power Usage - 37 vs. 50 Qt

BrianZ

We may be getting an ARB fridge soon, and I'm wondering if there is any difference in power usage between the 37 & 50 quart models.  Anybody know?

Also, any suggestions about what I might need to get in order to tie into the vehicle power and/or T@B battery for use with and/or without solar power.  Last time we were dry camping, we had solar on the TV roof connected to T@B during travel, so how could an ARB frig be connected - just to car battery & how?  Could I wire it to an unused 4-wire trailer plug on back of our car for power?  Seems like that would keep everything running while enroute with or without solar, plus car powering the T@B & ARB. 

Things seem more complicated at the campsite, depending on whether we could even use our solar at a shady campsite.  We plan to keep the ARB in the van, so if we were able to connect our solar to the T@B battery, then could we just just connect the 7-pin to car to maintain both batteries, like during travel?  Or, would we need to reconnect the ARB directly to the T@B battery?  I already have a NOCO charger pigtail that we could use if needed.  I suppose I could use a short set of solar cables & make a set of adapters to go from MC4 to NOCO and MC4 to whatever the ARB uses.

Any suggestions appreciated, as we don't have a lot of time before our next trip & there is an ARB available on sale locally.  For now, a quick & easy solution might work best.
Thanks.

JonW

I have a 41qt Indel B fridge/cooler connected to the trailer battery, and solar panels on the roof to continually charge the battery during daylight.  Simple connections and it works well.

The 12v fridge draw is not enough to drain the battery for several days sans charging.  Under normal dry camping or traveling the battery is fully charged by mid to late morning.

jkjenn

No idea about the difference, but if it is any help, I have the 37qt and Inwish I had the 50qt. The 37qt fills up fast.

Verna

I have two different 12V cords to from the ARB in the back seat of the Tacoma to an SAE plug (Zamp Plug) on the tongue box of the T@B 400.

One cord is the ARB official 15’ extension cord and I add an SAE plug to the end to plug into the plug on the tongue box.

The other is a Zamp official 15’ extension cord that I added a removable 12V accessory plug to the other end. 

I take either cord out the side window of the truck, and run it along the roof rack, then drape it down the rear of the truck to the tongue box. 

This is method has worked for 6 years for my 50 qt. Yes, I full time, but I’m still treating my food much the same way as I always have. Meat is on the bottom in the middle, where it will stay frozen. Veggies must be kept at the top, just under the lid. Yogurt will freeze if it falls to the bottom and it still tastes the same, but it is very liquid-dy. 

I did add a 12V official ARB extension cable from the Tacoma’s  battery to the rear seat. I added an in-line fuse at the battery, ran the cord through a plug in the firewall, tucked the cable under the floor trim to the rear seat. It works well with my new Tacoma Interstate AGM battery. 

I cannot help with the difference in the usage as I have had my 50 qt for 6 years. I notice no power usage overnight on my battery monitor. I do keep two flannel quilts over the ARB (be careful not to cover the ventilation holes in the ARB) to help with insulation, in addition to the stock ARB canvas cover with Reflectex in it. 

4ncar

My Indel b plugs in to 12v cig lighter outlet while driving or dry camping...

BrianZ

So, do I understand correctly that a 2-pin SAE connector will mate with the ARB's power cord? 
Also wondering if I can plug the other end of an SAE extension cord into a 4-pin vehicle trailer connector, since we have one available that is next to/wired to our vehicle 7-way, which has it's own cable to the battery.
The two pins at one side of a 4-way look like they carry the main power pair & might mate with SAE?
Thanks for all the great info.  I'm wondering whether the ARB cover is worth $125?

Verna

The ARB cover is worth the money. The more insulation you can add to it (blankets) in the summer, the less it has to work. 

The ARB cord comes with a 12V accessory plug (cigarette lighter plug). The SAE plug is an add on that I splice onto the ARB extension cord. 

The ARB extension cord comes with one end as bare wire so you can put whatever you want on it. Put a 4-pin plug on it instead of the SAE plug and you’ll have a stronger connection. Plus I don’t think the SAE plug will fit onto the 4-pin connection. 

My truck had no “always on” 12V accessory plug, and that is why I added my own.

Photomom

BrianZ said:

We may be getting an ARB fridge soon, and I'm wondering if there is any difference in power usage between the 37 & 50 quart models.  Anybody know?

Also, any suggestions about what I might need to get in order to tie into the vehicle power and/or T@B battery for use with and/or without solar power.  Last time we were dry camping, we had solar on the TV roof connected to T@B during travel, so how could an ARB frig be connected - just to car battery & how?  Could I wire it to an unused 4-wire trailer plug on back of our car for power?  Seems like that would keep everything running while enroute with or without solar, plus car powering the T@B & ARB. 

Things seem more complicated at the campsite, depending on whether we could even use our solar at a shady campsite.  We plan to keep the ARB in the van, so if we were able to connect our solar to the T@B battery, then could we just just connect the 7-pin to car to maintain both batteries, like during travel?  Or, would we need to reconnect the ARB directly to the T@B battery?  I already have a NOCO charger pigtail that we could use if needed.  I suppose I could use a short set of solar cables & make a set of adapters to go from MC4 to NOCO and MC4 to whatever the ARB uses.

Any suggestions appreciated, as we don't have a lot of time before our next trip & there is an ARB available on sale locally.  For now, a quick & easy solution might work best.
Thanks.

I can answer some of those questions when we get where we’re going and set up camp, maybe Monday. 

We have run a 50L ARB from the T@B battery, a Goal Zero Yeti, and a 12v port in the Highlander. And I’ve figured how to connect a Goal Zero solar panel to the Zamp port on the T@B. 

Photomom

Oh, I have a 50L and wish I had a 37L!

When REI had a coupon and I had dividends the 50 was all they had. Maybe I can work out a trade with someone at some point!

Photomom

Okay, DH is driving so I looked this up. This is the kind of thing you need to plug the ARB into the Zamp port of your T@B. You plug the 12v cord that comes with the ARB into this thing. YMMV,  but we swapped Zamp wires between battery terminals for correct polarity. There may be longer versions of this available, this plus the ARB cord was long enough for us to keep the ARB in the SUV because bears. 

https://www.amazon.com/KUNCAN-Motorcycle-Cigarette-Disconnect-Connector/dp/B01N7C0119/ref=mp_s_a_1_5?keywords=sae+extension+cable+kuncan&qid=1557581064&s=gateway&sr=8-5

jkjenn

Photomom said:

Oh, I have a 50L and wish I had a 37L!

When REI had a coupon and I had dividends the 50 was all they had. Maybe I can work out a trade with someone at some point!

Maybe we could work out some sort of deal?

BrianZ

Thanks, @Photomom, but why do you wish you had the 37 model?  I thought they had about the same footprint but one is taller?

BrianZ

Well, I was wrong about the 4-pin connector - there is no hot wire in it, just in the 7-way.  And our cig lighter socket just inside the back hatch of our Sienna van is not live.  Geesh.
So, trailer battery it is, unless traveling, then car socket I guess.

jkjenn

BrianZ said:

Well, I was wrong about the 4-pin connector - there is no hot wire in it, just in the 7-way.  And our cig lighter socket just inside the back hatch of our Sienna van is not live.  Geesh.
So, trailer battery it is, unless traveling, then car socket I guess.

Does your vehicle have a built in inverter? I also use my GZ Yeti battery for this.

Photomom

BrianZ said:

Thanks, @Photomom, but why do you wish you had the 37 model?  I thought they had about the same footprint but one is taller?

Weight mostly. I cannot lift it unless it’s empty. 

Photomom

BrianZ said:

Well, I was wrong about the 4-pin connector - there is no hot wire in it, just in the 7-way.  And our cig lighter socket just inside the back hatch of our Sienna van is not live.  Geesh.
So, trailer battery it is, unless traveling, then car socket I guess.

That’s one of the reasons we got the GZ Yeti, to keep the ARB running overnight when traveling. The 12v ports in our Highlander are only live when we’re driving. 

I will I’ll say that we have our good old Coleman cooler in the car now. The T@B fridge is acting up again and after all the issues we’ve had this week we decided to go low tech. 

Photomom

There there may be some useful information here for you. You can probably skip down to my Jan 31 update. 

https://tab-rv.vanillacommunity.com/discussion/8228/arb-fridge-freezers-vs-gz-yeti-update-new-gz-yeti-works-great-gz-customer-service-is-awesome#latest

JohnDanielsCPA

I bought two of the “official” ARB wiring harnesses.  One, I connected to my Jeep battery, ran it through the firewall, then to the rear and permanently attached it.  When we travel, we keep the ARB in the back of the Jeep and just plug in right there.  I bought a second harness that I wired onto the T@B battery.  I keep the cord rolled up in the propane tank.  Once we get to camp, I unplug from the Jeep and plug into the T@B wiring harness.  The T@B battery is kept charged with a solar panel, so I never run out of juice.  When we leave camp, I just unplug from the T@B and plug into the Jeep for our daily outings.  It’s just easier for us to keep the ARB in the Jeep all the time.  It also (somewhat) helps to keep it out of harms way from critters.  I’ve never run into a power problem.

BrianZ

Thanks again to all.  We too plan to keep the fridge in the van.  I ordered the cig lighter socket with SAE connector (thanks, @Photomom), which I plan to route out through the floor near the back & strap it next to the 7-way socket for powering from either trailer or car. 

From trailer battery, I can connect an SAE connector from a NOCO cable connected to a NOCO pigtail on the T@B battery in the tub while at the campsite with solar, or with solar on the car roof while traveling. 

Alternatively, I also ordered a 7-way plug, to which I plan to wire a short SAE cable, and then plug that into the nearby mounted SAE connector from the frig.  The 7-way connects directly to the car battery, so can be used to keep the frig running while making short trips or while camping. 

While traveling between campsites, we can have our rooftop solar plus frig each connected to the T@B battery with their own cables, as well as the car 7-way.  That's the plan anyway, so we'll see how it works out in the near future.

We picked up our new ARB 50Q today at a local 4-wheel store, on sale for $878.  Same footprint as the 37Q, but 3" taller.  The manual lists amperage as 5.1 for the 50Q and 5.0 for the 37Q, so power usage is very close, and I assume that is a max, as I've also seen the power listed at 0.87A for maintaining temp.

jkjenn

I can tell you that is the peak amp draw, but it is generally much lower....closer to under 2.5 amps.

BrianZ

I'm wondering about this 12V cord with the cig plug that comes apart..

The tip unscrews and contains a 15 amp glass fuse, while the collar at base also unscrews to provide a 2-pole plug..

Is this some kind of proprietary plug, or something else I am just not familiar with?  Is this designed to attach to ARB's own cord for hardwiring?  It looks like a miniature version of a common household AC plug.  The manual "highly recommends" it for a more secure connection.  Wondering whether it's the screw collar that makes it more secure, or are they implying better electrical contact?  If you use it, then you lose the fuse, so would need another inline fuse.  It's a bit strange.

While waiting for a bunch of miscellaneous wiring parts to arrive, I'm testing the empty fridge on AC power, and it cooled down very fast from room temp to 38 within 30 minutes.
Compressor/fan is rather quiet, and mostly after cooldown it is totally silent.  Looks promising. 

We'll see how it goes later at the campsite.  If we can't make use of solar for the T@B battery due to shade, then I'm wondering if we might be able to use the panel on the car roof for the cooler while parked at a sunny parking lot near a trailhead while hiking.  Would the car battery work with the victron controller (with a new profile)?  And how to wire it up?  Hmm, seems like a lot of work.  Don't want to become a slave to keeping the fridge running.  Maybe just driving around with it & letting the car charge the battery & shutting it off when parked.  Just don't want to get stuck with a dead car battery.  We should probably carry one of those battery jump start devices anyway.

Verna

@BrianZ, I won’t go anywhere without my battery jumpstart device that is just a bit larger than my iPhone. I have jumped more vehicles with it than I ever jumped with regular jumper cables. 

Since I upgraded my Tacoma’s battery, I leave the ARB plugged into the extra 12V accessory plug that I ran directly from the battery.  The ARB runs so little that I really don’t worry about it running the battery down. As long as your battery is strong, there shouldn’t be any problems. 

And remember that I’ve had my ARB for 6 years. Of course I’ve ran it more on the T&Bs’ (and Silver Shadow’s) batteries than on the truck battery, except for while towing. 

I’ll have to check the plug that you have figured out how to pull apart. I’ve never understood how to keep a tight connection while traveling, and it must be because I haven't dissembled the plug as you did. 

jkjenn

There are a lot of posts on various forums on the web about that design.ARB is an Australian based company so they do things a little differently. I

f you ever use a Goal Zero 12v outlet with, make sure you reach out to GZ for their little adapter, which they will send you at no charge or it wonwo work. I think the ARB plug is a little longer than the standard American.

BrianZ

I've seen pictures of the cig lighter plug, even on the outside of the box ours came in, which show a red plastic ring around the tip.  Our doesn't have any red colored parts - all black, but maybe it's just the tip I unscrewed to find a fuse inside.  It's the collar down near the wire end that unscrews to reveal another plug inside.
We don't have a GZ, or any other battery or generator, other than the car & T@B battery.
Car battery is less than 2yrs old & T@B is 150AH Trojan.

Photomom

BrianZ said:

I'm wondering about this 12V cord with the cig plug that comes apart..

The tip unscrews and contains a 15 amp glass fuse, while the collar at base also unscrews to provide a 2-pole plug..

Is this some kind of proprietary plug, or something else I am just not familiar with?  Is this designed to attach to ARB's own cord for hardwiring?  It looks like a miniature version of a common household AC plug.  The manual "highly recommends" it for a more secure connection.  Wondering whether it's the screw collar that makes it more secure, or are they implying better electrical contact?  If you use it, then you lose the fuse, so would need another inline fuse.  It's a bit strange.

While waiting for a bunch of miscellaneous wiring parts to arrive, I'm testing the empty fridge on AC power, and it cooled down very fast from room temp to 38 within 30 minutes.
Compressor/fan is rather quiet, and mostly after cooldown it is totally silent.  Looks promising. 

We'll see how it goes later at the campsite.  If we can't make use of solar for the T@B battery due to shade, then I'm wondering if we might be able to use the panel on the car roof for the cooler while parked at a sunny parking lot near a trailhead while hiking.  Would the car battery work with the victron controller (with a new profile)?  And how to wire it up?  Hmm, seems like a lot of work.  Don't want to become a slave to keeping the fridge running.  Maybe just driving around with it & letting the car charge the battery & shutting it off when parked.  Just don't want to get stuck with a dead car battery.  We should probably carry one of those battery jump start devices anyway.

ARBs are primarily meant for 4WD use and I believe the plug that remains after you unscrew the cigarette lighter plug part is for more of a permanent installation in a Jeep. Pretty sure there’s info in the owner manual. 

Be advised that if you ever decide to use the ARB with a GZ Yeti, the 12v plug won’t work. GZ will send you an adapter though. 

Photomom

During testing, the peak current draw that my Yeti showed was 60 watts when the ARB compressor and fan kicked on.

Sharon_is_SAM

@BrianZ, I believe that 2 prong plug is called a Heller or Hellar plug.  Here is the info from the ARB we purchased in 2016.

BrianZ

Thanks, @Photomom, 60W would be about 5A, so exactly what ARB lists as peak draw in their specs.
Thanks, @jkjenn, will keep the adapter in mind if I should ever get a GZ.
Thanks, @Sharon_is_SAM, I did find that page in the manual, but now I know what that plug is called.

We're going to stick with the fused cig lighter plug, and for that I got the SAE cord with cig socket from the amazon link above that @Photomom provided.  Yesterday, I wired the SAE end under the carpet in our Sienna's rear seat well and out through the same hole in the floor as or 7-pin wiring on back of our van.  I added some 3/8" split loom, then used two of the 7-pin mounting bolts to attach cable hangers to hold the SAE connector behind the 7-pin bracket, so the tip sticks out on one side & has waterproof connector caps.  Instead of using the NOCO charger pigtail, I'm going to wire in an SAE pigtail with thicker cable to the trailer battery in the tub & have a 12-ft SAE extension cord to run from T@B battery to the connector on back of car.  This will allow use of the bigger T@B battery & solar.  Nico's 10-ft extension cable looked a bit thin to me & specs don't include wire gauge.  SAE 12ft extension was noticeably thicker at 16G.

Alternatively (vs. plugging into a switched 12V socket in the back of the van, which is dead when the car is off), I will wire a short  SAE pigtail cable into a 7-pin plug, which can then connect the frig into 7-pin power that is wired directly to the car battery & always live.

BrianZ

Got the ARB wiring done today, as previously described..

The other end of the cig socket is mounted on the 7-way..

At 7-way an extension cable connects from the T@B battery.

SAE pigtail installed in tub & connected to extension to car.

We now have 5 fuses inside the bus bar box.

A 7-way plug wired to the end of the frig socket for powering from car battery.
All wiring tested & functional.

PS:  
When towing, with or without solar on car roof & connected to T@B, I plan to run the fridge SAE extension cable to its T@B battery pigtail in the tub.  Also plan to keep the T@B frig turned off as we normally do while traveling, due to its higher amp usage.  Probably wouldn't have to with solar plus car charging, but if camping without hookups I choose conservative.

BrianZ

Just a followup after our first trip using the ARB without hookups at campsite..
Everything worked fine using either/both wiring arrangements to power from T@B battery at campsite & while towing (with & without solar), or using the patch cord shown in last photo for powering from car battery while not towing or while parked away from camp. 

The extra load on the T@B battery was not all that noticeable really, with 50-ish temps at night plus Alde & fridge on propane.  We were able to get enough solar power to get back to 100% battery charge on a couple of days when I moved the panel into some small spots of partial or full sun. But mostly we could only get 10-15W at our nearly always shady site.  Still, all was fine.

The only issue we had with the ARB is that it wasn't keeping the temperature we set it for or that it was showing us on the display.  For example, when we set it to 30°, it might show it was 32, but our manual thermometer inside showed it was actually 40 or 42°.  It never seemed to be even close.  Adequate, yes, but not the ice cold drinks that we expected.  So, a bit disappointing, though still good use of energy.  Trying to imagine what people must set it to to get something to freeze.  
We did not have the canvas cover, by the way, which I understand improves efficiency, so maybe that is more like an essential part to get the results one might expect.  Disappointing that one may not get what they expect without it.

Verna

@BrianZ, have you coordinated the temp in the ARB to a known accurate thermometer?  The instructions are in the manual, and they might be on the under side of the lid, also.