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Wire sizing question for DC to DC charger…

OffRoadRN

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I am going to be installing the Renogy 20 amp DC to DC charger in my Land Cruiser and I am wondering what gauge wire to use? I am planning on mounting the charger in the rear of my vehicle and I think the run from the starter battery to the charger will be about 10-15 ft. I’ve been looking at different wire size calculators but don’t know what voltage drop is acceptable. Will 8 gauge wire be ok for this length of run and a 20 amp charger? Any benefits to using a larger gauge wire that is worse quality (I’m thinking 2 gauge copper coated aluminum jumper cable) instead of a smaller gauge, copper stranded wire?
 
I wouldnt recommend ccal in a mobile build... vibration will rapidly cause the wire to fail.
8 should be overkill for 20A i would think 10 would be fine. 8 for minimum voltage drop.
Be sure the wire is well supported, and go with fine strand cable.
Use rubber grommets anyplace wire passes through any bulkheads.
 
I’m struggling with the same question. I’m putting a DC-DC charger/MPPT type system in my Sprinter. Trying to figure out what gauge wire to run from starter to the DC-DC/MPPT (Renogy), as it is such a LONG run from starter battery to the place I put the battery setup (i know now it wasnt genius). A Sprinter is about 19 feet long, and then you have to add in for crossing the body and working around things. I know i need pure copper, but im trying to use appropriate gauge for a 25-30 ft run.
Any help?
 
I’m struggling with the same question. I’m putting a DC-DC charger/MPPT type system in my Sprinter. Trying to figure out what gauge wire to run from starter to the DC-DC/MPPT (Renogy), as it is such a LONG run from starter battery to the place I put the battery setup (i know now it wasnt genius). A Sprinter is about 19 feet long, and then you have to add in for crossing the body and working around things. I know i need pure copper, but im trying to use appropriate gauge for a 25-30 ft run.
Any help?
How many amps does it put out?
 
I’m struggling with the same question. I’m putting a DC-DC charger/MPPT type system in my Sprinter. Trying to figure out what gauge wire to run from starter to the DC-DC/MPPT (Renogy), as it is such a LONG run from starter battery to the place I put the battery setup (i know now it wasnt genius). A Sprinter is about 19 feet long, and then you have to add in for crossing the body and working around things. I know i need pure copper, but im trying to use appropriate gauge for a 25-30 ft run.
Any help?
I guess you have a pre 06 sprinter?
With the battery up under the hood?

As mentioned, first you need to know the amperage the unit draws.
Average is 30 to 50 amps.
You want from 0 to 5% loss, so use a dc wire size chart for the amps you have and choose the wire you can afford.
 
It is not advisable to use CCAL in a mobile build. The wire will fail quickly due to vibration. I believe that 10 would be sufficient for 20A, and 8 should be overkill. 8 is the lowest voltage drop. Make sure the cable is securely supported and use fine-stranded wire. Anywhere cable travels through a bulkhead, use rubber grommets.
Why have you just copied what @Supervstech said 5 months ago?
 
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