Will two AC300's handle my well-pump surge?

I’m trying to determine if I would be able to run my 230V well pump with two AC300’s connected through a P030A split-phase fusion box. But I’m not sure how to analyze my power measurements in conjunction with the equipment specs.

I clamped my ammeter around one 120V leg of the well-pump circuit, which I think measures the total current draw of the pump because the neutral is not involved in the 240V circuit. I measured 9A continuous with a 35.4A surge. I think this means that the total surge power draw is 35.4x240=8500W.

The overload specs for one AC300 are:
3100W < load < 3750W, 2min
3750W < load < 4500W, 5s
4500W < load < 6000W, 500ms

The P030A manual gives no information about overload or surge capacity - only that the steady capacity is 6000W @ 220-240V. In other words, the sum of the steady capacities of two AC300’s.

So if each AC300 has a surge capacity of 4500W for 5 sec. and 6000W for 500 ms, doesn’t that mean that the total surge capacity for the 240V output of the P030A would be 9000W for 5 sec. and 12000W for 500 ms? Wouldn’t the surge capacities be expected to add just like the steady capacities do? If so, my well pump’s 8500W surge would presumably be okay.

“Winnie” at Bluetti told me:

The surge current 35.4A exceeds the maximum current of the AC300 30A. So I think it will not work.

But that seems like the easy answer because it doesn’t even consider the surge capacity of the AC300’s - only the steady output.

I don’t want to just gamble on buying two AC300’s, two B300 batteries, and a P030A because Winnie also told me that if it wouldn’t run my well pump I would be responsible for shipping all 300 pounds of equipment back to the warehouse.

I’d really appreciate any guidance this community could give me on this question.

I’m in the same boat. I have a well with a 230V well pump. Instead of waiting I pulled the trigger and got the two AC300, B300 combo with the P030A. I figured that they system was powerful enough to run everything else in my house so I’m keeping my fingers crossed it will hand the well pump. I figured the same thing you were thinking, if there was 6000W continuous from the system then I should still get the benefit of the surge capacity as well.

I’m still waiting on the P030A which isn’t due to show up until later this month. All I can say is I’m going to test it when I finally get the P030A and see how it goes. I’ll be sure to post my results.

Thanks. I’ll be very interested to hear about that.

Can you either measure the surge amps or find it out from the manufacturer and post it here? That will help me and other people determine how applicable your situation is to ours.

You may be interested to know that although your post just shows your login ID the email notification that I got from Bluetti shows your full name. That’s kind of distressing. I assume that you will get a notification about this post of mine. Does that notification show MY full name? (If so, please don’t repeat it here!)

If you connect 2xAC300 split phase together, the surge current would also double assuming the power is pulled evenly from both phases, which it should in this case. The question is how long does it surge for. I think there is a high chance of things working if the surge is only a couple seconds long.

Now, I don’t know how you are measuring the surge but most multimeter only updates once a second so you may or may not pick up higher power but lower durations surges.

Did you ever receive your P030A? Do you have any experience to share yet?

Not yet, supposedly it’s coming soon (late May is what they have on their website). Not sure if that’s believable given the situation in China right now. Keeping my fingers crossed.

Thanks. Perhaps they’ll meet their new timetable. Good luck!

I’m not sure if you can use this on a well pump, but for other large appliances like an AC unit you can get a soft starter box.

It’s probably silly to ask, but did the P030A ever show up?

Have you considered a slow start circuit added to the well pump? It works by adding a resistive load inline for a few seconds to limit that surge current. The pump will start but slower, then while it is running at a slower speed, the resistive load is switched out and full power is applied after the smaller surge has passed. In a layman’s term the slow start breaks the inertial of the motor with less power and then later accelerates it to full power. If it was an automobile, it is like accelerating slowly, then after the automobile is running about 20 to 30 MPH for a few seconds you accelerate to 50 or 60 MPH. In a real automobile you lose time and burn less gas if you drive that way, but the fellows behind you will be honking their horns!

Extra: To see the surge current with an ammeter, try to get an analog version or a extremely good digital meter with a peak memory option. The analog meter can show the surge as the needle swings up rapidly, then drop to the constant reading. I still keep one even if I have a good digital meter with a peak memory option (it is called “MAX” on some multimeters), and works in both AC and DC circuits.

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Thanks for your suggestion. I don’t actually have a problem at this point since I only have one AC300 and of course can’t run my 240V well pump with that. I want to see what experience other people have in running well pumps with two AC300’s and the P030A split-phase fusion box before I go in any deeper.

And an extra response: I’ve got a Klein CL440 meter with an excellent inrush (or surge or max) function. It’s only $100 on Amazon right now - I paid $109 in March.

Nice automobile analogy!

It did show up, thank goodness! However, I had a trip scheduled so I haven’t had a chance to try it out. I have a 30amp generator transfer switch that is already wired to my main panel. Going to try and plug it in there and see if runs the well pump. I’ll turn off the other breakers to make sure I’m not exceeding the max wattage. I’ll definitely report back after my test.

Any joy yet? [This part is to satisfy the 20-character minimum.]

I had intended my post the other day as a reply to you but I see that it wasn’t. This time I’ll make sure it’s to you!

Have you had a chance to try this yet? Although I haven’t searched exhaustively, so far I haven’t run across someone saying that he’d actually been running his 240V well pump off two AC300’s and a P030A.

Any new information yet about running your well pump?