gatorgrizz27
Well-known member
Hi all, I’m working on adding auxiliary wiring/power circuits to my LR3. At this point, I don’t want a dual battery system, so I’m planning on running a portable battery box with a deep cycle marine battery when needed. Here’s the basic plan, hopefully it’s legible.
I have an 80 amp fuse on the battery terminal, with 8 gauge wire running to a Blue sea fuse block under the dash. These fuses will be hot constantly. Running out of the fuse block will be another length of 8 gauge wire going back to a continuous duty solenoid which will be connected when the ignition is on, a 40A circuit breaker, and a 50A rated plug at the rear of the vehicle for maintaining trailer batteries. I realize it won’t fully charge a battery, I have a NOCO genius charger for that, it’s just to help out on longer trips.
At this point, I’m not running a fridge, but I’m going to wire for it so it can be plug and play. I have an ARB fridge socket, which will be powered off the fuse block and 10 gauge wire. I’d like to use this Blue Sea 3-way switch with an ignition triggered relay.
This would allow me to have the fridge socket turned off (bottom position) when no fridge is connected, hot when the ignition is on (middle position) for daily use, and be able to turn it on momentarily (top position) when the vehicle is off. I was thinking this would come in handy at camp after the vehicle has been off awhile and you’ve been in and out of the fridge making dinner. Once everything is put away, turn it on and let it run until it cools off again to sit overnight. Obviously you have to make sure you turn it off again, I also carry a NOCO lithium jump starter.
Thoughts so far?
The second half of this is a portable battery box, carried only when needed. It will be simple, basically just the battery with heavy leads wired to an Anderson connector. The lid will have another ARB fridge plug, 12V socket, USB sockets, and another 50A rated plug for the battery charger or adding some charge via the plug on the back of the car and alternator. I didn’t draw a circuit breaker/fuse on the positive lead, but it will have something there.
This would be brought along on longer trips where the vehicle might be parked for longer, or we want to run the fridge all night. It can be inside the vehicle with the fridge, and plugged into a battery charger if we are in a state park campground with electricity. It could also be used in other vehicles not wired for the fridge, or brought into a hotel room and recharged.
I have a few questions, the first is about safety when charging it inside the vehicle. I won’t be sleeping inside it, so charging would be via the alternator while driving, or plugged in on the charger with no one in it. Theoretically, noxious gasses can be produced, but I have a pair of deep cycle lead acid batteries in my cargo trailer that sits on the charger closed up, and I have never noticed any odor or corrosion/evidence that harmful gasses are being produced. Obviously, I could use an AGM or even lithium battery, but it’s quite a bit more expensive.
The second is if I built a jumper lead from the ARB fridge plug in the vehicle to the input plug on the box, would it pass enough current to keep up with the demand of the fridge running off the box through the 10 gauge wiring? Obviously, the rear plug will be able to send more, but it would be nice to not have a heavy wire running across the cargo area sometimes.
Finally, do the grounds from the rear 50A vehicle plug or fridge plugs need to be run back to the battery negative, or is a good chassis ground sufficient?
Any other advice, pitfalls, things I haven’t considered are appreciated.
I have an 80 amp fuse on the battery terminal, with 8 gauge wire running to a Blue sea fuse block under the dash. These fuses will be hot constantly. Running out of the fuse block will be another length of 8 gauge wire going back to a continuous duty solenoid which will be connected when the ignition is on, a 40A circuit breaker, and a 50A rated plug at the rear of the vehicle for maintaining trailer batteries. I realize it won’t fully charge a battery, I have a NOCO genius charger for that, it’s just to help out on longer trips.
At this point, I’m not running a fridge, but I’m going to wire for it so it can be plug and play. I have an ARB fridge socket, which will be powered off the fuse block and 10 gauge wire. I’d like to use this Blue Sea 3-way switch with an ignition triggered relay.
Amazon.com: Blue Sea Systems SPDT Remote Control ON-Off-ON Contura Switch for ML Automatic Charging Relays : Industrial & Scientific
Amazon.com: Blue Sea Systems SPDT Remote Control ON-Off-ON Contura Switch for ML Automatic Charging Relays : Industrial & Scientific
www.amazon.com
This would allow me to have the fridge socket turned off (bottom position) when no fridge is connected, hot when the ignition is on (middle position) for daily use, and be able to turn it on momentarily (top position) when the vehicle is off. I was thinking this would come in handy at camp after the vehicle has been off awhile and you’ve been in and out of the fridge making dinner. Once everything is put away, turn it on and let it run until it cools off again to sit overnight. Obviously you have to make sure you turn it off again, I also carry a NOCO lithium jump starter.
Thoughts so far?
The second half of this is a portable battery box, carried only when needed. It will be simple, basically just the battery with heavy leads wired to an Anderson connector. The lid will have another ARB fridge plug, 12V socket, USB sockets, and another 50A rated plug for the battery charger or adding some charge via the plug on the back of the car and alternator. I didn’t draw a circuit breaker/fuse on the positive lead, but it will have something there.
This would be brought along on longer trips where the vehicle might be parked for longer, or we want to run the fridge all night. It can be inside the vehicle with the fridge, and plugged into a battery charger if we are in a state park campground with electricity. It could also be used in other vehicles not wired for the fridge, or brought into a hotel room and recharged.
I have a few questions, the first is about safety when charging it inside the vehicle. I won’t be sleeping inside it, so charging would be via the alternator while driving, or plugged in on the charger with no one in it. Theoretically, noxious gasses can be produced, but I have a pair of deep cycle lead acid batteries in my cargo trailer that sits on the charger closed up, and I have never noticed any odor or corrosion/evidence that harmful gasses are being produced. Obviously, I could use an AGM or even lithium battery, but it’s quite a bit more expensive.
The second is if I built a jumper lead from the ARB fridge plug in the vehicle to the input plug on the box, would it pass enough current to keep up with the demand of the fridge running off the box through the 10 gauge wiring? Obviously, the rear plug will be able to send more, but it would be nice to not have a heavy wire running across the cargo area sometimes.
Finally, do the grounds from the rear 50A vehicle plug or fridge plugs need to be run back to the battery negative, or is a good chassis ground sufficient?
Any other advice, pitfalls, things I haven’t considered are appreciated.
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