How far is too far for the inverter?

OK, back to the OP's question:

Wire gauge is dictated by three things:

Length of run (distance= length of BOTH positive and ground).

Amp draw-- that is why the question about what watt inverter. Correct answer for a 300 watt inverter would clearly not work for a 2000 watt inverter.

Acceptable voltage drop. For some circuits, a 10% voltage drop under maximum load is acceptable. For "primary" circuits and inverters, 3% is an acceptable figure.

Here is a good discussion and chart showing correct wire choices: http://www.westmarine.com/WestAdvisor/Marine-Wire-Size-And-Ampacity

2oldman wrote:
2 gauge wire at that distance running a MW may not work.

hermandutchman wrote:
did you and Gordon even read what the op posted?

LOL.. what's up with that?

No idea just messing around, thought Midnight was too. It's not like the topic of inverter wiring comes up all that often, wanted to inject a little levity. :B

pianotuna wrote:
Hi,

How many watts is the inverter?

Also how big is the battery bank and battery type for how low an SOC can it be down to before the loaded voltage hits the 11v inverter alarm set point?

Then pick how low you might be down to when you want to run the appliance. My own requirement is to be able to run the toaster for early breakfast when the batteries are down to 50% and due to be recharged later that day.

Your inverter to battery distance is easily doable with the right set-up, so the distance itself is not an issue.

If you are pulling 1500W from an inverter for the microwave you could be pulling as much as 150A from the battery bank taking into account an 85% inverter efficiency. That would translate to ~2.5% voltage drop over a 12 ft run (back and forth), more with low-quality lug connections.

But with respect to ampacity (cable over-heating), the charts I've seen recommend #1 at least for 150A. Perhaps #2 if you only go up to 120A.

Hi,

How many watts is the inverter?