Three new AC200P units - one holds less charge?

So we have three new AC200P units (wish I would have waited a bit and got one of the new MAX or 300’s - bummer).

When running the same chest freezer, one of them runs out of power faster. Over nite one will have 60% left in the morning, the other 40%. I am trying to check times close so I have a good measurement.

Is this variation normal, or do I have one unit that’s not right?

Hi there,

The freezer’s inner temperature, opening times, capacity, and what is in the freezer will consume different power. Please try and see what will happen when these are the same.


Another thought to add, have you done a calibration of the batteries and battery management? I have read a number of posts talking about doing this to get accurate battery level information. As I understand it, you fully charge the unit, then put a load on and let it run down until it turns off. After that you can charge it again, but now the battery management system has “learned” the real battery capacity. Maybe that will help the results.

The other thought is to run the freezer multiple times on each unit and average the results to see if that better accounts for variations in freezer operation, load, and openings.

If you buy a Kill A Watt P3 plug in meter, you can accurately measure the amount of power consumed by the freezer. This will give you real numbers to know exactly what is occurring.


I second @hnymann 's suggestion. My AC200P gave me a scare at one point by refusing to charge to charge past 87%. I believe the battery was actually full but the metering had become off. I discharged it to zero and then back to 100% and now it seems to be sorted out.

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Thanks - I have been running them on the same chest freezer. One unit 7 AM to 7 PM, and the other on the opposite 12 hour shift, and that’s where I see the difference.

I’ll try running to zero and charging, to calibrate.

Is there a market for barely used, like new AC200P’s? I really need more battery - am hoping the B230 can connect and be charged by the AC200P - but I have yet to get a clear answer on this.

@markieboy711 Both of B230 and B300 can connect and be charged by the AC200P. You will need a D050S to connect them.