2nd Battery Cable Gauge Question

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Viking1204

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I've decided I want to install a 2nd battery setup in my F-150 Supercrew. From the battery to the back of the truck in a straight line where I plan to put the battery it's 19'. I plan to run the cable down to the frame, under the truck and then up through a small hole in my bed, probably be about a 25' run when done. My question is what gauge cable should I use to run from my engine compartment to the battery at the back of my truck? I'm thinking 2 gauge welding wire should do the trick. The reason for welding wire is it uses smaller strands of copper making it easier to work with, also means more copper than standard battery cable with thicker wires. Have any of you ran a similar distance and if so what gauge have you used successfully?
 

smritte

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You didn't specify why you were running it. I'm going to assume you don't ever want to start the vehicle with it. This is the gauge I run for my rear accessories. Fridge, compressor, feed to charge trailer battery and a few small items. I use a 50amp resettable breaker and a small fuse panel in the back to separate everything. Make sure you install a larger body ground to match. Most vehicles run a 10-12 gauge body ground. I run 2 gauge.
Very good choice using welding cable too. I make all my battery cables out of it.
 

Viking1204

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You didn't specify why you were running it. I'm going to assume you don't ever want to start the vehicle with it. This is the gauge I run for my rear accessories. Fridge, compressor, feed to charge trailer battery and a few small items. I use a 50amp resettable breaker and a small fuse panel in the back to separate everything. Make sure you install a larger body ground to match. Most vehicles run a 10-12 gauge body ground. I run 2 gauge.
Very good choice using welding cable too. I make all my battery cables out of it.
My plan is to use it like you are. Long term plan is to get a refrigerator, short term I'll run my water pump off it and power some LED lights most likely. I hunt in the middle of 2000 acres of pine forest so having a power source at the back of the truck will be useful. I'd like to have an inverter back there and at least a couple A/C outputs. I'll charge it with a solar panel or two.
 
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My plan is to use it like you are. Long term plan is to get a refrigerator, short term I'll run my water pump off it and power some LED lights most likely. I hunt in the middle of 2000 acres of pine forest so having a power source at the back of the truck will be useful. I'd like to have an inverter back there and at least a couple A/C outputs. I'll charge it with a solar panel or two.
Yes on 2 GA. A cable made for starters, will carry all the power you will need, without choking down or worrying about heat issues from 'currant'. You should be able to find cable that size and length at a electrical outlet store, or maybe a big rig repair shop. The connector's are cheap to purchase.
 
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Blue Seas Systems.com has a chart for cable length and current. I would recommend covering your run with split loom. It will give the cable extra protection plus a clean looking install. Blue Seas also makes fuse connectors that mount directly to the battery for an easier install.3290D364-DAF4-4B60-93BF-BBE0EB89B99F.jpeg
 

smritte

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My plan is to use it like you are. Long term plan is to get a refrigerator, short term I'll run my water pump off it and power some LED lights most likely. I hunt in the middle of 2000 acres of pine forest so having a power source at the back of the truck will be useful. I'd like to have an inverter back there and at least a couple A/C outputs. I'll charge it with a solar panel or two.
At the rear of mine I have a power port and a 4 amp usb. I use a 12 volt led landscape light mounted on a painters pole. That thing is so bright I had to put it above eye level. I have a 120 watt panel. For what my drain is, its actually overkill.
Im running this circuit breaker in front. The 50 amp. Breaker
 
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I've decided I want to install a 2nd battery setup in my F-150 Supercrew. From the battery to the back of the truck in a straight line where I plan to put the battery it's 19'. I plan to run the cable down to the frame, under the truck and then up through a small hole in my bed, probably be about a 25' run when done. My question is what gauge cable should I use to run from my engine compartment to the battery at the back of my truck? I'm thinking 2 gauge welding wire should do the trick. The reason for welding wire is it uses smaller strands of copper making it easier to work with, also means more copper than standard battery cable with thicker wires. Have any of you ran a similar distance and if so what gauge have you used successfully?
is your battery a lithium or acid battery?