Inverter experts needed

My recent experience does not make me an expert, but here is what I found.

First, many factory inverter installs are hotwired directly to the inverters. Even if you have a truck power disconnect switch, it might not depower the lines to your inverter. TEST THIS.

Second, Freightliner wanted to charge me some insane price for direct engineer involvement to put my inverter on the truck disconnect circuit.

Third, most decent inverters have fuses or breakers as part of their design. Mine uses standard automotive blade fuses.

In the end, for my inverter install, I had a second manual rotary disconnect switch installed next to the Freightliner factory disconnect switch. The only thing on that circuit is the inverter.

Now, if I have inverter issues again, the unit can be completely depowered without impacting anything else on the truck in any way, and I can even replace the unit myself, later, if needed, without worrying about battery cables shorting during removal/install.

 

Might want to check your math. Most 12v sockets are rated for 15 amps. That's 180 volts.

 

You would be correct. Thats what mine are rated for but i barely go over 100.

 

This is the scary thing, you need to understand what the purpose of the fuse at the BATTERY is their for. Those internal fuses are there for the control electronics to prevent a meltdown of the circuits, not for the safety for the truck to prevent a fire.

 

How is this working? The quality of that wiring and kit looks really good but the cables seem pretty small to me. I would definitely go bigger than 4 gauge for any inverter 2000 watts or more. I've used this kit on 2 inverter installs. Good quality and great price, and you get to support everyone's favorite trucker Jeff Bezos! (couldn't resist)

https://www.amazon.com/gp/product/B017VBMHRO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

Just came yesterday, hadn’t installed it yet.

That kit you bought off Amazon looks really nice. Much cheaper too! Thanks for sharing.

 

Okay. I am no electrical expert by any means, but explain more clearly why fuses in the device are less effective than fuses in-line.

Assume the circuit is a single simple circuit. Batteries connected to inverter in one, single loop circuit.

The only issue I can think of is that in a spectacular enough failure, there might be damage around the fuse. That would damage the device if the fuse is in the device. The chances of that are very close to zero if the fuses are properly rated.

I am being 100% serious here. Explain, please, why I need to be worried.

 

The battery fuse is so that if/when something connects between the cables, either something wears through the plastic protection at the terminals, or something rubs through the cable insulation, and connects that circuit, it doesn't burn your truck down.

Fuses in the device do nothing to protect against a short between the cables.

 

Don't know if it's already been mentioned, but you want your cables to be as short as possible. The longer they are, the more power you will lose. 3-4 ft is optimal, but not always possible. I think mine are about 5ft.

Also you might want to check the amperage of the alternator on your APU. I once had one with a 60 amp alternator and blew it out a few times. I think most of the newer ones have 120amp.

 

There is already a factory fuse protecting the battery bank itself. I will check to see if it will disable the inverter circuit.