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My 1 ton Minisplit A/C will not start on a 12volt 5000 watt inverter

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gnoeld

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I have 9 12 volt 100Ah Lead Acid Marine deep cycle Batteries.
a 5000 watt Pure Sine Inverter
The AC will not start. The inside unit works but the outside (compressor) will not start.
I thought I had plenty of power
What's up?
It works fine on Grid power
 

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There is no such thing as a real 5kW 12v inverter.

nine 12v 100AH marine batteries in parallel will supply a 2kW 12vdc inverter.

If battery cabling is large enough you might start a 12 kBTU inverter minisplit. Common for 120v mini-splits not to have power factor correction which makes it iffy for a 2kW inverter and 12kBTU mini-split. Just its inverter power supply rectifier-capacitor surge current may cause inverter to shut down.

Most 240vac 12 kBTU mini-splits have power factor correction.
 
Last edited:
5000W 12V inverter?
Please show us the inverter and the spec, and the wiring you are using.
 
gnoeld said:
Okay but if you look at the specs on the AC unit it looks like a 3000 watt inverter would work
Click to expand...
The compressor start up power surge can be from 4 ~ 7 times the running rated power and the length of surge may last longer than the so called surge rating of the inverter which usually only in 30 ~ 50mS..
 
I have run into this problem myself. The issue is that the spec on your HVAC does not include inrush. Most HVAC compressors have a minimum of 6 times the run current value. Some go as far as 10 times. Your inverter is not 6 times more powerful than your HVAC.

FYI .. this is why low frequency inverters are popular. They often can hold overcurrent by 20 seconds or more.
 
Bud Martin said:
The compressor start up power surge can be from 4 ~ 7 times the running rated power and may last longer than the so called surge rating of the inverter.
Click to expand...
 

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@gnoeld: I am running that particular inverter - it is a high frequency inverter, not a low frequency inverter. It only holds surge loads for 20 milliseconds. So you need to find a unit that can sustain around 9000 watts for 20 seconds or more.
 
1. The cables aren't big enough for 360 amps.
2. You don't have enough battery for that kind of surge.
Start up will be a lot higher than running amps. (Look up LRA for that unit)
 
My wire is 2/0 and I have 9 100Ah batteries. How much more do I need?
 
gnoeld said:
Is there anything else that I can do other than buying a new inverter?
Click to expand...
It's all about that inrush current. I have not been able to run my HVAC either with that inverter and I am running 4/0 cable. I will be replacing the inverter...
 
Years ago I had a 6000w 12v inverter.
Couldn't hardly power anything, unless the engine was reved up continuously.
 
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