AC200P with external B300 battery, first tests

Have only had it a couple days but so far I’m liking the B300.

First couple discharges were encouraging. Got around 4000wh the first time and 4,100wh the second, both were drawing a constant 750 watts from a space heater. That’s around 80% efficiency from the 5,072 claimed combined watts. The AC200P by itself would usually get me a little over 1,600wh.

Recharge times for the B300 battery were 7 3/4 hours with a 500w wall charger or 5 1/2 hours using the 500w charger plus a 200w wall charger going through the 200w PV port.

One glitch I’m a little concerned about is the battery shut itself down during the first discharge at about the 4 hour mark still showing a 20-40% charge remaining. I restarted it and it went all the way to empty with no other issues. The case felt cool to the touch so probably not a heat issue. It discharged the entire 100% the second time with no shut downs.


The third full discharge test was with a residential gas furnace and two full size fridges. It went a total 21 hours and produced 3,700wh which averages out at about 176 watts per hour. Somewhere in the middle I shut the system down for the night and then resumed the next morning so it wasn’t running the 21 hours straight.

Unfortunately the battery shut itself down 3 times during the test, the first time was again around the 4-5 hour mark and a second time at another 4-5 hours from that.

I wonder if the B300 has some sort of auto time out if its not connected to an AC300 or Max and the DC isn’t turned on?

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My B300 battery definitely has a 4 hour auto shut down. Tested it again today with a 300 watt load coming out of the AC200P and at exactly 4:01 hours from startup the B300 shut down. Not good if you need it for more than that and aren’t around to reset it.

That test was done without the DC circuit for the USB’s and cig lighter socket turned on. I’ll do another 4 hour test with the DC on to see if that makes any difference.

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Was just looking at the AC300 manual online and saw that it has a 4 hour eco mode.

Several notes from the manual:

" ECO Mode: A power saving mode for the AC300+B300. The AC output ports
are automatically turned off if the load is less than 30W over a span of 4 hours."

“AC300+B300 will turn off in 4 hours under:
a: No Input and Output b: AC and DC switch at OFF state”

I guess the battery can’t sense the power going out of it without an AC300 hooked up to it.


It is interesting to put the 4hr eco mode auto shutdown logic on the B300 battery and make it the job of the connected ACxxx to override it. One would have thought the battery would stay on until told to shutdown by the connected ACxxx. It must be pretty important for it to turn off. Did anyone check idle consumption of the battery?

Well the DC power button being turned on seems to be the key. I ran it for over 5 hours yesterday without a shutdown and to double check will test it for over 12 hours today.

Sure is fun being a beta tester, virtually zero info in the B300 manual.

How does the charging work? I was watching a YouTube channel (Dave Prowse) and he was saying that you have to charge the AC200P separately from the B230… does this problem exist with the B300?

I managed to get both the big light and small lights blinking at the same time. Below is how I did. Connect the charging cable between B230 and AC200. Turn off B230 and turn on AC200. Connect the AC charger (T500) to B230 trying to charge it. At this moment, since B230 is not turned on, B230 is not being charged yet. Now long press B230’s power button till it flashes. Both AC200 and B230 are now being charged and both the big light and 5 small lights are blinking. Try it. (solution found by another user in the community RogerD)

Sure you could do it that way but I’d bet it would take longer than doing each one individually. I would assume there is some wattage lost in the transfer from the B300 to the AC200P and both units would be on longer so wattage would be lost that way also. Probably not a big deal for AC charging but it would be for solar where every watt and minute counts.

It might be interesting to try it both ways to see how much difference there would be.

In my case I have enough AC chargers or solar panels to do them separately but at the same time.

OK!! Just for clarity….

  • B230 is OFF and AC200(x) is ON
  • Connect the Charger (T500) to the B230
  • Long press the power for B230
  • Both lights should be blinking (big and small set)

Yep, that should work. If the B230/300 is at 0% then it may take a little while for it to reach a certain charge state before it begins charging the AC200*. It was 10-15 minutes on my B300.

Just completed a 12v DC discharge test of my B300. At a 100 watt constant draw I got 2500wh in a little over 24 hours for an 81% efficiency rate.

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Would you recommend the 300 vs the 230?

I went with the B300 thinking that someday I may upgrade to an AC300 and from I’ve read the B230 won’t work with them. The extra 1,000wh is nice to have as well :slightly_smiling_face:

Down side might be its weight and size, at 80lbs its a load!

Ok. I was under the impression that the batteries were cross compatible with all the ACxxx generators. If that’s not true, I’ll definitely pick the 300 over the 230.

The info I had back in September when I pre ordered was that the B300 was cross compatible with the AC200Max/AC300 but the B230 wasn’t.

Edit: Or maybe it was you couldn’t have a B230 and B300 in the same system?

Hi @eric102 @Whiplash2130,

B230 can not work with AC300. If you want to connect more than 1 batteries, you need to make sure that batteries are the same model. B230 and B300 can not connect with any unit simultaneously.

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I actually have the AC200Max. Would you recommend the AC300 vs. the 230 and why?