Accessory Battery Low Voltage Disconnect

The big new electrical upgrade I am going to get for my truck is the low voltage disconnect for the accessory battery. At times I leave a load on the accessory battery which drains it too low and causes premature failure. I am replacing the accessory battery every two years because of the excessive drain damaging the chemistry in the battery, and I believe that a proper low-voltage battery disconnect would maintain battery life much longer, and also reduce wear and tear on the alternator.

When installed, the battery would be disconnected from any of the accessory loads when the voltage dropped below 12.1 volts for more the 30 seconds. The battery would remain disconnected from the accessory load until the system voltage reached 13.5 volts for 30 seconds, e.g. when the alternator was running. This way if I left the CB Radio on, the inverter on, or just left the truck parked for multiple days with the load of USB chargers and other slight drainers, there would be zero discharge of the battery beyond a safe point. This would ensure that I get the maximum capacity out of the accessory battery for as long as possible.

Replace the Accessory Battery (Again)

This will be the third accessory battery on my truck, after replacing the first one after three years and replacing the second one after two years. It’s not a big deal as marine batteries are cheap – about $90 – and it provides a lot of light and enjoyment for camping. Remember when gas prices were $4 a gallon, it was a $90 fill up in truck. Lead acid batteries are almost fully recycled into new batteries. But I’m getting tired of having to replace the battery. I’m hopeful – actually quite certain – that the low voltage cut-off, along with improvements I’ve made to the charging system over the years will mean much longer lifes for the batteries going forward.

Hook Up Dash Camera to CB Radio Switch

One important project that I got done over the weekend – required no additional supplies is to connect the USB ports adapter I have to the CB radio power switch I installed in the truck last summer. This way the dash camera can be easily switched on an off, and won’t get left on draining down the battery. Unlike the current system I have that uses an extension cord, hooked to a USB port, this connection should be tighter, and less prone to disconnecting when driving over bumpy back roads.

Better switches in the truck cap

I have this inexpensive switch box that I got from Walmart a few years back but the switches are crap. They don’t always work reliabilty and the wires are always pulling loose. I am reaching a better switch box for this purpose and with eventually replace the switch box with it come spring. I want to easily be able to control the many different lights in the truck cap, without having to fiddle around with switches that are unreliable and constantly being tightening up wires. 4-6 10 watt switches in one unit are ideal. I am going to look on Ebay or Amazon to figure out which switch box to buy.

Install Dimmer Switch for Truck Cap

I also want to install a low-voltage dimmer switch for the truck cap. LED lights work decently with widely available low-voltage pulse modulation dimmer switches, assuming that the pulse modulation is quick enough to not be visible to the human eye (e.g. more then 30 cycles per second). Most modern dimmers designed to work with LED lamps work decently for this purpose. Some older dimmers don’t work, but for the most part they aren’t designed for 12 volt lighting.

More LED Lighting?

I already have a lot of LED lighting for the truck cap. But I am always keeping my mind open to new possibilities, especially as prices come down, and efficiency improves. I like having lighting in the cap that illuminates the things that need to be illuminated but don’t waste power.