Inverter wireing ? (1 Viewer)

[450 DUDE]

Hey guys , just have a quick question.
Im installing a 1000w inverter in the aft cargo area.
Im trying to get away with not running the neg. wire all the way back to the battery. I would like to do a short neg run from the inverter to a good frame ground.
is this a bogus idea ? can I get away with this? drawbacks?


thanks in advance, ken

 

[Rubiconcruiser]

Inverter wiring

Bad idea to shorten the ground wire, this is the return link to the power source, and the chances of destroying the inverter or torching the rig is expotentially guarnteed. The ground must show an even wave length in as well as out of the battery or it overheats thinking nothing is wrong.

 

[lovetoski]

Bad idea to shorten the ground wire, this is the return link to the power source, and the chances of destroying the inverter or torching the rig is expotentially guarnteed. The ground must show an even wave length in as well as out of the battery or it overheats thinking nothing is wrong.

I'm confused. I'm no electrical engineer, but know a little about circuts, and have always understood them in comparison to a loop. Make a continous loop, place the load anywhere w/in the loop (assuming properly sized wires to minimize voltage drop) and you're good to go. I'm not saying your info is wrong - just that in many years of amatuer electrical work, I've never seen this idea. With my inverter, I ran the ground to a nearby body location. However, I have multiple ground connections between body/frame/battery, so I know I have a good ground anywhere in the truck.

School me, I'm OK with it. Where should I look for more info to better understand what you are saying? ('cause I don't quite get it yet...)

 

[450 DUDE]

Thanx for the response, good points, I think I still might be over simplfing
the return path . It seems thatif I hit a good frame ground it would be as good as a wire. conductor is a conductor, right am i missing something?

thanx again in advance ken

 

[DieselROCKS]

Yeah you could do it that way but something could happen. You're already running one wire, why not run another and be sure that you will always have a good ground.

Just like wiring a winch, you wouldn't ground to the frame. For the cost and time you could save by just doing it....just do it

Cheers
Geoff

 

[hoser]

Isn't the starter motor grounded to the frame?

 

[Pin_Head]

A 1000 Watt inverter is going to sink about 80 amps of current at full load, so you are going to need some beefy cable. There is no problem with the frame handling this current, but the connections need to be good, just like the battery ground.

What's this stuff about being on the right wavelength?

This is a DC circuit.

 

[450 DUDE]

hUMMM.... good stuff. Ya I was kinda thrown by wavelength?
thought I migth be missing something.
Im running #2 cable with marine crimp on lugs.
Seems as long as I get a good frame ground I should be ok.?
The reason Im not running @ wires Is because IM cheep and space issues.
BUT i DO NOT want to cause a hazzard.

thank again ken

 

[CruisinGA]

Like pinhead said-
as long as the inverter to frame ground is good, AND the battery to frame ground is good, there is little/no difference between running an actual cable.

The problem is with corrosion over time, less tha perfect connections, etc.

 

[desertdude]

Also check your inverter ( install manual) requirements for distance from the battery - if you are going a farther distance than suggested you might need to up the wire size. Also be sure and add a high amp fuse link between the battery and the inverter.

 

[450 DUDE]

I did the wire size calcs. and im using a marine circut breaker @ the batt.
good note on the corrosion, I will be going out of my way to make that a sano
connection. I also will be adding a couple bonding straps.

Anything else?

BTW , by my #s a decent remote Inverter set up, double the cost of the actual invter for a complete job



Thanx again guys , ken

 

[Romer]

Geee, This is a different kind of electronics than they taught me when I got my EE. Hmmmm, pinhead is correct. You don't need to run a wire all the way back to the battery, BUT it needs to be a good ground.

And if the negative post on your battery isn't electrically the same point as the ground on the Frame, you have a bad ground connection and need to fix it.

yes you can tie the negative cable on your winch directly to the Frame, AGAIN, if it is a good ground.

A good ground is defined as less than 1 ohm resistance between the frame and the negative post on your battery. low milli-ohms is better.

A poor ground becomes a resistor.

 

[tech_dog]

I'm contemplating the need of the ground wire myself. One data point is my 400 amp warn winch, which warns in the owner's manual that the ground must go to the negative post of the battery.

I'm not sure at what point grounding to the chasis is a problem. Back to google....

 

[mobi-arc]

Chasis ground is presumed poor, unless proven otherwise. It especially becomes an issue as you get into higher current.

 

[450 DUDE]

Just a quick update, install complete and field tested.
Decided to nix the ground wire to the battery but I made two bonding straps
and installed them from neg post to body and frame
I havent flogged the thing yet but so far works good.

btw the #2 pos lead ran in the left side frame box from under drivers seat area all the way back.




ken

 

[srplus]

for curiosity

to preface, i am no EE; but have been in the electrical sign business forever. why not locate the inverter close to the battery and run your 110 plugs where ever you want them on the truck with # 10 wire. you could even use exterior waterproof romex that is made for burial... should have no voltage drop with # 10 and you could have plugs where ever you wanted them. use exterior waterproof boxes and if i am not mistaken (correct me if i am wrong here) and you do it right you, could make the plugs ground fault. This setup would be much cheaper and give you all the outlets you wanted, exactly where you wanted them.

this is the way my huge one on my crane truck is set up. i have an extension cord on an automatic reel that when plugged into the inverter gives me 110 at the work basket.

 

[hoser]

srplus, running the inverter close to the battery and running longer AC lines is the preferred way to do it but there is no good place to mount the inverter in the engine compartment (too much heat, moisture). However, you can mount your battery and inverter in the rear... but then it takes up excess space.

 

[srplus]

i am dealing with this issue right now in my fj60. have a 2000 watt and am trying to figure out if there is a good space under the hood to put it or if i should go with an under the seat install w/ romex to where i want the plugs. the two main issues for me are: 1) space under hood (a little crowded with all the vacuum hoses in there and i am planning on second battery install), and 2) when fording streams or mud holes would it be high enough not to cause a problem electrically... for this was thinking for sure an inline cut off with the fuse setup. regardless, i know i do not want to be sleeping in the back of my truck with a battery back there. have just kept it under the seat and opened the hood and clamped it up since the only time i have wanted the 110 from this inverter has been when i was stationary. but for the long haul that setup is not acceptable.

jpgs of someone else’s install under the hood would be great.

 

[hoser]

Mounting your inverter under the hood where temps reach 130+ degrees would kill your inverter in no time. Mounting it under your seat would be better. The rear quarter panel (if there is space) might be best. Just run 0 or 2/0 gauge power wire to it (and the necessary fuses).

 

[97 FZJ80]

I believe the topic of underhood installation of the inverter has been covered before. Due to the underhood temperature exceeding the operating temperature of most inverters, it was not advisable to located the inverter in the engine compartment.