really dumb inverter question

[Jeep or Tacoma]

Do I put the fuse on the positive line ? can i just put the ground directly to the neg terminal on the battery? I have a mod sine wave 800 watt inverter and am hooking it up. I want to use a 100 amp fuse I think just off the positive side of the battery about 1 foot away? I am running the wire #4 gage through the bottom of the Jeep's passenger side? and wiring the inverter in under the passenger seat. Do I need to cut the carpet away? I am not sure how much air space the thing needs. please make your answers simple that last time I did E-work on a car it still had points and condensers! Thanks all

 

[wrcsixeight]

Fuse on the Positive, close to the battery as is feasible without excessive effort. Make sure the wire cannot possibly chafe and ground out between the battery and the fuse.

How hot the inverter get sis variable on how much you are asking from it. 800 watts is significant. ~ 63 amps @ 12.6 volts DC not including inefficiencies.
I have a 6 year old, Coleman 800 watt MSW inverter. I have powered a 5.5 amp A/C (55 amp DC) angle grinder for a long while. The inverter got warm, not hot, but I could trip the alarm if I intentionally leaned heavily on the tool while under load.
Put the inverter as close to the batteries as possible, over the fattest wire you might need in the future. If you find 800 watts is not enough, figure considerable effort and expense required to replace and re run 4AWG with with 2AWG.
Use household 120 volt ac cords to distribute the AC juice where you need it. Do not use long runs of inverter to battery cable unless you absolutely have to, or plan on never using the 800 watts the inverter can provide, with the initial amperage roughly, possibly, twice that, briefly, depending on the appliance.

 

[Tennmogger]

By all means fuse the negative cable also. If your vehicle's ground connection to the battery fails for any reason (like simply a dirty connection), high current through the starter will seek the route: chassis to inverter box to inverter neg wire to batt ground term.. not good. Would probably fry your inverter.

Being so close to the battery is an excellent location, electrically!

Bob

Do I put the fuse on the positive line ? can i just put the ground directly to the neg terminal on the battery? I have a mod sine wave 800 watt inverter and am hooking it up. I want to use a 100 amp fuse I think just off the positive side of the battery about 1 foot away? I am running the wire #4 gage through the bottom of the Jeep's passenger side? and wiring the inverter in under the passenger seat. Do I need to cut the carpet away? I am not sure how much air space the thing needs. please make your answers simple that last time I did E-work on a car it still had points and condensers! Thanks all

 

[gabepari]

By all means fuse the negative cable also. If your vehicle's ground connection to the battery fails for any reason (like simply a dirty connection), high current through the starter will seek the route: chassis to inverter box to inverter neg wire to batt ground term.. not good. Would probably fry your inverter.

Being so close to the battery is an excellent location, electrically!

Bob

I've always wondered about the legitimacy of this practice. While some devices recommend fusing the negative, I'm not sure it is safe for all...

Some systems behave extremely erratic when there is no ground connection. If there were a situation that caused the negative fuse to pop, the device might still self destruct.

Maybe it would just be better to make sure that vehicles grounding system is solid. In particular the engine to chassis ground, that's the one that will reek havoc if it fails.

My $0.02 (you get what you pay for )

Gabe

 

[BigJim]

ALL my Ham radios

Come with fuses on the pos and the neg. Some radios draw 20 Amps DC. I say it IS a good idea to fuse both legs. Also read the manual on grounding for the 120 VAC side.

If you short the DC side without a fuse you'll need a hatchet or bolt cutters to break the wire. You will also have a huge light bulb filament wanting to burn your truck down.

I've always wondered about the legitimacy of this practice. While some devices recommend fusing the negative, I'm not sure it is safe for all...

Some systems behave extremely erratic when there is no ground connection. If there were a situation that caused the negative fuse to pop, the device might still self destruct.

Maybe it would just be better to make sure that vehicles grounding system is solid. In particular the engine to chassis ground, that's the one that will reek havoc if it fails.

My $0.02 (you get what you pay for )

Gabe

 

[SunTzuNephew]

Radios are fused on both sides because of the risk that an antenna (connected to ground) will become energized and the path to ground will be through the radio negative power lead.