Hardware Home built battery box with dew heater controller

I purchased a Camco 55373 Large Battery Box from Amazon along with the power ports, volt meter and switches (main power and the lights). The LED lights were sourced at a local automotive parts store.

I recently had to replace the battery (AGM) that was over 4 years old as the run time was getting short on it. I purchased a new Power Queen LiFeP04 50Ah (640Wh) battery from Amazon. This battery is about 1/2 the weight of the old battery and provides 14Ah more capacity. It cost more than an AGM or gel battery, but since I also carry the rig in the RV with us when we go out, every pound saved means either more water or food in the trailer for when we are boondocking.

The Camco box is equipped with two switches. One is a master power switch that activates power for the outlets and any other attached devices. This switch also has a red LED indicator to prevent impacting night vision. The volt meter is also a red LED and mounted to the front of the box to be easily viewable but not in direct line of sight. Also, the main power switch is only rated at 5 amps... so I put in a 30 amp relay that is controlled by that switch to get more power distribution.
Inside the box the master power switch goes to a 8 way blade fuse block holder which then distributes power to the various outlets and devices and each has its own fuse. There is also a master fuse between the switch and the battery positive terminal of the fuse block (can't be too careful).
I also added 4 5v USB female ports to allow to use any USB-C or older powered devices I may need to attach to. The downfall of these are that they are 5v over BOTH ports.. so you can only use one of them if you need the full 5v use (like with an RPi 4).

You can see the 4 12v adapter plugs (the ones in the original configuration have been replaced by non-switched ones that have no LED illumination when activated that I obtained at the local WalMart in the automotive area) that I am currently using.

External USB & 12v plugs.JPG

I will be posting better images of the internal wiring shortly after I clean it up a bit.

Internal Wiring on box top.JPG

I installed 2 red lights (controlled by a switch) for when I'm in a dark area so that i can have some light around the mount/battery but not negatively impact vision that badly.


You can also see the volt meter that I installed.

One note about your main power switch. Most of them of the size I am using are limited to 5AMPS of draw. To get around this (and not have to use one of the large gaudy 20AMP switches) I placed a relay in between the power switch and the main power feeds. That way, the 5AMP switch is not overloaded as all it does is turn the power on through the relay.

I have some 5.5x2.5mm plugs received from Amazon to attach to the battery box to allow me to directly hook the Intel NUC's up to power with them. For my primary scope I will need to get a 6 foot cable, but that is low priority since currently I have a Pegasus PBBADV hooked up to it that does the central power and a 12 volt cable that supplies power to it. These plugs (photos will be added once the equipment arrives) are more for the smaller rig that I mount the BeeLink NUC to the mount leg.
I also have a pair of 5.5x2.5mm M/M cables on order for use now.

Specifications for the box as outfitted
Battery Brand: Power Queen
Battery Model: LiFePo4 12.8V
Deep Cycle: Yes
Amp Hour: 50Ah
Watt Hour: 650Wh
Number of power ports: 7+
Red light functions: Yes
About author
I've been interested in astronomy since I was in Jr. High (graduated in the early 80's).
It wasn't until I retired that I was able to really get into it due to monetary and time constraints.


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Tracy Perry
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