HELP! Dometic Drawer Fridge Wiring?

[OVRLNDER]

I hope this should go here. If not can the mods please move. I pulled the trigger and purchased the Dometic Drawer fridge (like the one @Michael bought) . I have tried to figure out the graph in the manual to wire it up, but I can’t for the life of me understand what gauge wire I should us since it will be in the back of my 4 door Wrangler (JKU). I have contacted Dometic and they have only told me to look at the graph in the manual (screenshot below). I figure with how I’m going to run the wire, maybe 10 to 12 feet of power wire (going to run ground to frame), so what gauge wire should I use?

 

[Sparksalot]

I hope this should go here. If not can the mods please move. I pulled the trigger and purchased the Dometic Drawer fridge (like the one @Michael bought) . I have tried to figure out the graph in the manual to wire it up, but I can’t for the life of me understand what gauge wire I should us since it will be in the back of my 4 door Wrangler (JKU). I have contacted Dometic and they have only told me to look at the graph in the manual (screenshot below). I figure with how I’m going to run the wire, maybe 10 to 12 feet of power wire (going to run ground to frame), so what gauge wire should I use?
View attachment 146037

Use this graph to find the recommended size in mm square, then convert to AWG.

American Wire Gauge (AWG) Cable Conductor Size Chart / Table

Table of the American Wire Gauge (AWG) Cable Conductor Sizes. The AWG Table includes cable diameter, maximum current capacity in amperes, resistance and frequency skin depth / skin effects

www.diyaudioprojects.com

 

[OVRLNDER]

Use this graph to find the recommended size in mm square, then convert to AWG.

American Wire Gauge (AWG) Cable Conductor Size Chart / Table

Table of the American Wire Gauge (AWG) Cable Conductor Sizes. The AWG Table includes cable diameter, maximum current capacity in amperes, resistance and frequency skin depth / skin effects

www.diyaudioprojects.com

I’ve tried that, my problem is trying to see where my points on the graph line up. Say Im at 12 feet (3.66 meters roughly), where on the graph to I line up with.

 

[Boostpowered]

Run #4 to #0 size line to a distribution block you wont have to worry about how long the wire is from the battery then run a shorter fused wire that matches what your fridge requires to the dist block. With the block you can add more electronics if needed #0 will handle well over 600 amps if that helps any. Another thing is the quality of the wire you use, not all gauges are equal say you have 2 different 16g wires one may only be good for speakers the other may have better shielding and insulation allowing to be used for more amps.

 

[OVRLNDER]

Run #4 to #0 size line to a distribution block you wont have to worry about how long the wire is from the battery then run a shorter fused wire that matches what your fridge requires to the dist block. With the block you can add more electronics if needed #0 will handle well over 600 amps if that helps any. Another thing is the quality of the wire you use, not all gauges are equal say you have 2 different 16g wires one may only be good for speakers the other may have better shielding and insulation allowing to be used for more amps.

That was going to be my last resort, I used to do this for subwoofer set-ups back in the day. I eventually plan on having a solar set up on the Jeep and run the wire to those batteries (which would be closer). Since I’m out of work cause of this pandemic, I don’t know when I’ll be able to do the solar set-up.

 

[Boostpowered]

That was going to be my last resort, I used to do this for subwoofer set-ups back in the day. I eventually plan on having a solar set up on the Jeep and run the wire to those batteries (which would be closer). Since I’m out of work cause of this pandemic, I don’t know when I’ll be able to do the solar set-up.

I think its the best way especially if you plan to add more draw than just the fridge. Makes sense i used to do db drags on the side in my late teens early 20s.

 

[Prerunner1982]

Maybe this will be easier to understand.

 

[OVRLNDER]

Well, I went with running a 4 gauge wire to an auxiliary fuse block. I'm just waiting for the 100 amp circuit breaker to come in and I'll be up-n-running. I will eventually increase the circuit breaker when the time comes but with just the fridge for now, I figured 100 amp breaker will do. Thank you for everyone's help. Much appreciated.

 

[smritte]

How long is your wire run? If your talking 20 foot, a 100 amp breaker may be too high. If you get a big enough short, you don't want your wiring getting hot. I'm running a 4 gauge feed to the rear of my cruiser for my fridge and my trailer. One battery on the trailer, 50 qt fridge on the trailer, 20qt in the cruiser. My power draw hasn't topped 45 amp. I ran a 60 amp breaker on mine.
When I was working in the field, wring was one of my specialties. I've seen enough burned wiring from improper fuse sizing. I normally run one size larger wire and fuse it by the max draw not wire capacity. People tend to see what the max is and go to the extreme. If you want to see improper wiring and heat, drop your lower dash panel, run your ac fan on high and grab the wire going to the fan ( the 12 gauge). Most run warm to hot. The manufacturer run their wiring to max spec. Over time it starts melting back the insulation from the terminals and over heats the connectors.
The chart above allows 3% voltage drop. 100 amp @ 20 ft with 4 gauge wire. That means they allow a 3v drop @ 33.33 watt loss and that comes to 113 btu of heat. Obviously that's 100 amp continuous which is not going to be run but, with a 100 amp breaker the surge will be considerably higher than that before it pops.
I guess all the time I spent reworking peoples "professionally done" wiring has made me cautious. Personally I would calculate current flow and fuse it by that.

 

[OVRLNDER]

How long is your wire run? If your talking 20 foot, a 100 amp breaker may be too high. If you get a big enough short, you don't want your wiring getting hot. I'm running a 4 gauge feed to the rear of my cruiser for my fridge and my trailer. One battery on the trailer, 50 qt fridge on the trailer, 20qt in the cruiser. My power draw hasn't topped 45 amp. I ran a 60 amp breaker on mine.
When I was working in the field, wring was one of my specialties. I've seen enough burned wiring from improper fuse sizing. I normally run one size larger wire and fuse it by the max draw not wire capacity. People tend to see what the max is and go to the extreme. If you want to see improper wiring and heat, drop your lower dash panel, run your ac fan on high and grab the wire going to the fan ( the 12 gauge). Most run warm to hot. The manufacturer run their wiring to max spec. Over time it starts melting back the insulation from the terminals and over heats the connectors.
The chart above allows 3% voltage drop. 100 amp @ 20 ft with 4 gauge wire. That means they allow a 3v drop @ 33.33 watt loss and that comes to 113 btu of heat. Obviously that's 100 amp continuous which is not going to be run but, with a 100 amp breaker the surge will be considerably higher than that before it pops.
I guess all the time I spent reworking peoples "professionally done" wiring has made me cautious. Personally I would calculate current flow and fuse it by that.

What size breaker would you recommend?

 

[smritte]

Do some rough calculations to see what your draw is. Personally, if you have 20 ft of cable, I would err on the low side and run a 50 - 60 amp breaker.
My 50qt fridge can draw 6-7 amps when it's hot outside, my smaller one a bit less, say 5 amps. A low battery on my trailer can draw 40 amps. With that i'm looking about 50 max, that's why I went with a 60 amp breaker. I can surge 65-70 before it pop's. These allow for current surges so don't worry about spiking when a fridge starts up.
You also need to make sure your terminals and block can flow enough. I get my higher current terminals from my welding shop and they get staked, soldered and shrink tubed.

 

[smritte]

Forgot this. Circuit protection is based on wire size and length, not current. Wire size and length is based on power flow. Figure out what your requirements are, go a bit higher just because, choose wire and match circuit protection.

 

[Incalescent]

I’m trying to do something similar, wiring the drawer fridge to a dc cigarette male so I can run it off a Ecoflow RiverMax. I probably only need 3’ of cord. Does anyone have any idea what gauge I need? Will 16 gauge do it? I can find plug adapters on Amazon and they’re all 16 gauge. I saw another website with 14 gauge one.

 

[M Rose]

I’m trying to do something similar, wiring the drawer fridge to a dc cigarette male so I can run it off a Ecoflow RiverMax. I probably only need 3’ of cord. Does anyone have any idea what gauge I need? Will 16 gauge do it? I can find plug adapters on Amazon and they’re all 16 gauge. I saw another website with 14 gauge one.

My fridge has 10 gauge wire to the cig lighter adapter stock from the factory… I cut off the stock plug and went to an Anderson Connector because the cig lighter adapter kept falling out of the socket, and the stock vehicle wire to the socket is only 18 gauge. So I upped to double ought wiring from my battery bank (located under my hood) to my auxiliary electrical box in the rear of my rigs. But I went overkill because all of my lights, air compressor, fridge, radios, water pump, and other electrical accessories run off of the auxiliary electrical system.

 

[ganthercage]

My fridge has 10 gauge wire to the cig lighter adapter stock from the factory… I cut off the stock plug and went to an Anderson Connector because the cig lighter adapter kept falling out of the socket, and the stock vehicle wire to the socket is only 18 gauge. So I upped to double ought wiring from my battery bank (located under my hood) to my auxiliary electrical box in the rear of my rigs. But I went overkill because all of my lights, air compressor, fridge, radios, water pump, and other electrical accessories run off of the auxiliary electrical system.

great temporary solution until u bring someone more professional to figure it out

snaptube vidmate ​

 

[slomatt]

The original post in this thread is over a year old, but does anybody else find it surprising that Dometic seemingly referred a customer in the US to a graph using metric wire gauges and lengths? Given their expansion into the US market I'd hope they now also provide a graph using AWG and feet.

If anybody is interested you can convert the wires cross-sectional area (in mm^2) shown in the Dometic chart to AWG using a table like this one. And Google will convert from feet to meters for you (or just divide meters by 3.3).

Looking at Dometic's chart of wire size for 12v over a 10' run (3 meters) they recommend a wire size of ~6mm^2, which is 10 awg. According to Blue Sea's chart this can support 25-30A.

 

[Incalescent]

The original post in this thread is over a year old, but does anybody else find it surprising that Dometic seemingly referred a customer in the US to a graph using metric wire gauges and lengths? Given their expansion into the US market I'd hope they now also provide a graph using AWG and feet.

If anybody is interested you can convert the wires cross-sectional area (in mm^2) shown in the Dometic chart to AWG using a table like this one. And Google will convert from feet to meters for you (or just divide meters by 3.3).

Looking at Dometic's chart of wire size for 12v over a 10' run (3 meters) they recommend a wire size of ~6mm^2, which is 10 awg. According to Blue Sea's chart this can support 25-30A.

this seems excessive. The draw of the drawer fridge is supposed to be 3A. Why do you suppose Dometic makes this recommendation?
My current thinking is I’ll get a cigarette lighter adapter with 3’ of 14ga with Anderson connections and wire Andersons to the loose ends on the drawer fridge to connect to the Ecoflow River Max. Safe?