Can you guys look over my plans for hardwiring a power inverter?

[Andrew Clope]

Just to update this thread, replacement Whistler inverter arrived yesterday. I installed it and it worked perfectly. Just a faulty inverter before.

 

[Jason Russell]

Just to update this thread, replacement Whistler inverter arrived yesterday. I installed it and it worked perfectly. Just a faulty inverter before.

Good to hear! Make sure you get the earth ground off the chassis though- it will cause noise issues with electronics.

 

[Andrew Clope]

You mean the case ground? Where should it be grounded?

 

[Justin Wilcox]

You want to keep the ground as short as possible. no longer than say 18". A few more inches doesnt hurt really. If you have to ground to something like the trunk or any interior framing, running a separate piece from the body to the frame anywhere on the vehicle will be fine. Also, make sure you remove any paint where your ground is going to be. You can do it however you want, as long as the metal is exposed and clean. Ive done this when installing 30k watt car audio systems, so..

 

[Matt Tottle]

I know this is pretty much solved but I want to address a couple of things..

First, NEVER put a fuse in the ground lead unless specified by the manufacturer. Anything that actually COMES with fuses in both or specifies such, are designed for installation in both negative ground and positive ground vehicles - and as such all chassis components are isolated from the electrical ground. If you install a fuse in the ground of a device with a non-isolated chassis (one that specifies a positive fuse, and/or has the disclaimer "12V Negative Ground Only"), if that ground fuse blows or otherwise becomes defective, it will seek ground through the mounting bolts, antenna connections, RCA connections, ground prong of an inverter, etc - which will cause a dangerous situation in the form of a shock/fire hazard and will possibly destroy the device and others that are interconnected. For most automotive devices today, you only install a fuse in the POSITIVE lead, and said fuse MUST be within 18 cable inches of the battery, inside the engine compartment. Ground leads must be as short as practically possible, and never more than 18". The only time you run negative back to the battery is with radio gear (as in ham, not stereo), because the battery acts as a filter against ignition noise.

And second, you should only be using the inverter for devices which you have no other choice but to use it.. Using it to power a laptop, ipad, cell phone charger, etc is just dumb - because aside from the square wave issues, you're stepping the 12V up to 120V and creating a mangled AC wave, only to step it back down to 5-20V and rectify the mangled AC wave back to DC, which does nothing but waste power on conversion. Buy car chargers for your devices and use those. They are much more efficient. And yes there are plenty of laptop car chargers (universal and brand-specific) - even though most laptops require 18-21 volts. They contain step-up circuitry that draws extra amps to boost the voltage. Make sure you install quality/heavy duty hardwired cigarette lighter sockets on their own fused circuit - especially for the laptop adapter. The cheapo triple adapter sockets will melt on you, and your existing cigarette lighter/power port will probably not be able to handle the load.

 

[Justin Wilcox]

Lol yeah dont fuse the ground wire haha. And for tip #286 - Fuse for the wire, not the equipment.