General question about 12 volt inverter hookup in vehicle

[kellys_eye]

I'll be damned, the instructions. I knew I forgot sumpin...

We get a lot of those AI comments on here recently. Just ignore them.

 

[wjbell]

We get a lot of those AI comments on here recently. Just ignore them.

10/4

 

[kellys_eye]

=2.5

 

[wjbell]

UPDATE:

Well I got it all installed with the new wire. I've got one grommet on the battery side that I can go through and there's just no way to fit two 1/0 gauge wires through there. So for now I had to do a short ground to the seat mount. This is just temporary, later I'm going to have to drill through the floorboard and run the ground under the body and up into the engine compartment and the battery. Running the microwave works just fine although I do have to start the engine to get the alternator involved. The positives to the battery get a little warm but not hot at all. I'm wondering if a negative lead directly to the battery will keep me from having to start the truck and keep the positive leads from getting warm?

 

[kellys_eye]

At such high currents you need the cleanest and shiniest surfaces on ALL the connectors plus a good pressure (torque) via clean nuts, bolts and washers.

The introduction of even a fraction of an ohm resistance results in heat - where ever you get heat, revisit the connection and all it comprises.

Not sure of the actual battery you're using in the truck but a starter motor will pull anywhere from 50A to 150A (usually around 70A) and even at that amperage will cause the terminal voltage to drop to around 10 or 11V - really depends on the health of your battery. This is why you're having to start the engine first - to supply the additional amperage/volts to keep the inverter input voltage above its 'shut down' (or non-start) level.

 

[kellys_eye]

'm wondering if a negative lead directly to the battery will keep me from having to start the truck and keep the positive leads from getting warm?

No, the problem is - as I said above - the actual connection points. The bolt on the seat runner NOT getting hot means it's a GOOD connection!

Problem with 'remote' earths (via the chassis) is that the return to the battery is all the way through the vehicle body and THEN through the battery-to-chassis wiring (sometimes a simple braided cable) which could be a point of failure if the total current through it exceeds its carrying capacity. Remember, the electrical wiring is designed for the VEHICLE to operate properly, not add-on accessories and especially not accessories that demand such massive currents!

Nice crimped connectors though

 

[wjbell]

No, the problem is - as I said above - the actual connection points. The bolt on the seat runner NOT getting hot means it's a GOOD connection!

Problem with 'remote' earths (via the chassis) is that the return to the battery is all the way through the vehicle body and THEN through the battery-to-chassis wiring (usually a braided cable) which could be a point of failure if the total current through it exceeds its carrying capacity. Remember, the electrical wiring is designed for the VEHICLE to operate properly, not add-on accessories and especially not accessories that demand such massive currents!

Nice crimped connectors though

No, the problem is - as I said above - the actual connection points. The bolt on the seat runner NOT getting hot means it's a GOOD connection!

Problem with 'remote' earths (via the chassis) is that the return to the battery is all the way through the vehicle body and THEN through the battery-to-chassis wiring (sometimes a simple braided cable) which could be a point of failure if the total current through it exceeds its carrying capacity. Remember, the electrical wiring is designed for the VEHICLE to operate properly, not add-on accessories and especially not accessories that demand such massive currents!

Nice crimped connectors though

The inverter has a warning beep when the input voltage drops too low. I can run the microwave through the inverter without starting the engine at first. The microwave will go about a minute before the inverter starts beeping. And it will go about 2 minutes before the inverter shuts down. So usually when it starts beeping I start up the truck and either the beeping stops or it still beeps but it won't shut down.

The battery is about a month old. And if I remember it's a 650 or 700 CCA battery. The ground connection to the seat I took out the bolt and filed the underside of the bolt clean and wire brush the threads so I have a good solid ground there. All the lugs, washers and bolts our new. I could use to wire brush the terminals on the inverter and where it connects to the battery. They are a little iffy. But I think the main source of any heat on the positive cable is because of the length of wire then I'm running from the battery to the inverter. It's about 5 ft. Is that right, length of wire will increase heat to the wire? I can't get any heavier of a gauge

 

[wjbell]

Nice crimped connectors though

Oh yeah, I was going to solder them but I don't have a torch big enough to heat it up enough. So I bought this hydraulic crimper at harbor freight. The things a beast! It has dies on from one gauge all the way down to 14 gauge. Works perfect. $75 though

 

[kellys_eye]

The proper tools are never cheap.

The whole cable would be getting warm of there was an issue with its c.s.a. (cross sectional area) so you're ok there.

Without checking the manufacturers data (discharge curves) on that battery, even at 150A draw a one minute use will discharge only 2.5 amp-hours from the battery. Not a lot in the scheme of things and it shouldn't be enough to cause a low battery alarm. Perhaps the battery isn't up to spec or maybe fit a 'diesel' battery?

Monitor the battery voltage during the off and on cycles - the battery should remain over 10.8V (ideally over 11V) for just a minutes use of the inverter.

 

[sarika78]

"Installing a 12-volt inverter in a car might be a practical method to power small electrical gadgets on the road. To minimize excessive drain on the vehicle's battery, ensure appropriate installation. Always utilize proper gauge wiring and secure connections to ensure safety and dependability while enjoying the benefits of portable power."

Thank you guys,
for sharing such good information, for lots of love, and amazing things that you have contributed.

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