diy solar

diy solar

How about Using a 1-Phase 120V to 3-Phase 240V Converter Instead of Parallel Inverters?

If you are running it off of your single phase gen then you DO NOT HAVE A 3 phase motor and cannot use a single phase inverter to three-phase inverter Money down the drain.
That information right there is worth the price of admission. You and @Supervstech have helped in that regard. Obviously the pump is really single phase or it would burn up, which leaves me wondering why PenTek's spec sheet clearly states that it is a 3-phase motor.
 
There's a puzzle piece I was missing. I've heard the phrase "soft start" tossed around (the tech from Pentair mentioned it, but didn't know what it was) but you're the first person to indicate that it is something that can be programmed into some inverters. Now I need to check my proposed inverter to see if it has that feature. FYI, I'm currently looking at an MPP L6548.
That only applies to single-phase to three-phase inverters to drive a motor. Does not apply to power inverters.
 
That information right there is worth the price of admission. You and @Supervstech have helped in that regard. Obviously the pump is really single phase or it would burn up, which leaves me wondering why PenTek's spec sheet clearly states that it is a 3-phase motor.
That pump series comes in a huge variety of HP and you will need the catalog # to get the right spec sheet. You may not have the right spec sheet

Download the spec sheet
 
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That pump series comes in a huge variety of HP and you will need the catalog # to get the right spec sheet. You may not have the right spec sheet

Download the spec sheet
That's the sheet I am working off of. Only thing I can figure is that the guy who installed the pump made a mistake when he told me what it was. He installed it last year. I called him about it a few weeks ago to get the model number and he did not remember it, but he said it was 3 phase. He did not say 3 wire. I think he goofed. It's obviously single phase if it runs of my generator. So hopefully that makes it easier for me? Can I use a split-phase AIO to generate 240V that will work with the pump? Or, for that matter, a single-phase 120V inverter through a transformer?
 
That's the sheet I am working off of. Only thing I can figure is that the guy who installed the pump made a mistake when he told me what it was. He installed it last year. I called him about it a few weeks ago to get the model number and he did not remember it, but he said it was 3 phase. He did not say 3 wire. I think he goofed. It's obviously single phase if it runs of my generator. So hopefully that makes it easier for me? Can I use a split-phase AIO to generate 240V that will work with the pump? Or, for that matter, a single-phase 120V inverter through a transformer?
That I cannot tell you. One horsepower pump needs 750 watts to run but needs 3 to 4 times that to startup
 
That I cannot tell you. One horsepower pump needs 750 watts to run but needs 3 to 4 times that to startup
I just meant, assuming the inverter has enough power to handle the startup surge and then some, are there any other hurdles to getting something like a split-phase 120V/240V inverter to run a single-phase 240V pump? I am specifically considering the MPP LV6548, which seems like it ought to have enough power with 6.5kW output.
 
Seems like or ought to have are meaningless variables in physics. Do you know the start up Amps of your pump?
PenTek tech support said 19.6A to start (without soft start) and 4.9A to run it, but there is some question about the exact model. We originally believed it was a 3-phase motor (per the installer) but since it runs from our single-phase generator, it appears to be a single-phase pump. So if it's a PSC 2-wire motor, it could be as high as 7.9/9.1 (full/max-SF) load. If its a 3-wire motor, then it could be as high as 8.4/8.4/0 (Y/B/R, Full Load) or 9.7/9.7/0 (Y/B/R, Max-SF Load). That's all from the spec sheet.

That said, I worded my question poorly. Although I said that the inverter should handle the load, that was an aside. The real question is, assuming an inverter has enough power, are there any incompatibilities or problems running a single phase 240V well pump from a split-phase 120/240 AIO?
 
any incompatibilities or problems running a single phase 240V well pump from a split-phase 120/240 AIO?
Earlier answers suggest the motor should run fine on 240 volts Nine Amps (2.2kW) startup sounds like it is not too much for a 6kW inverter
 
Earlier answers suggest the motor should run fine on 240 volts Nine Amps (2.2kW) startup sounds like it is not too much for a 6kW inverter
Thanks for the feedback. Forgive my ignorance, but I'm trying to figure out where surge amps come into the picture. For example, the PenTek model P42B0010A2 is a 1HP 0.75kW 230V pump, which is listed at 7.9A "Full Load" and 9.1A "Max/SF Load". I don't know what those numbers indicate, but I've heard people say that surge/start draw is 3-5 times running draw. Which number, then, would I triple or quintuple, and shouldn't that be the number to measure against the inverter?
 
I don't know what to tell you? Maybe what you told me about startup Amps is wrong. I had assumed startup and surge were the same. I am not going to be much help because I cannot read your mind nor do I have the pump in front of me. Apparently it is at the bottom of your well.
 
I don't know what to tell you? Maybe what you told me about startup Amps is wrong. I had assumed startup and surge were the same. I am not going to be much help because I cannot read your mind nor do I have the pump in front of me. Apparently it is at the bottom of your well.
I initially told you 19.6A startup. My understanding is that startup and surge are the same. That's why I didn't follow you when you said 9A.
 
Thanks for the feedback. Forgive my ignorance, but I'm trying to figure out where surge amps come into the picture. For example, the PenTek model P42B0010A2 is a 1HP 0.75kW 230V pump, which is listed at 7.9A "Full Load" and 9.1A "Max/SF Load". I don't know what those numbers indicate, but I've heard people say that surge/start draw is 3-5 times running draw. Which number, then, would I triple or quintuple, and shouldn't that be the number to measure against the inverter?
Full load amps are your normal running amps, SF amps are slightly overloaded amps, and Surge amps are called Locked rotor amps
 
Well, a 19Amp start is consistent with a 5 Amp load to run it but now you are saying 9 Amps to run it? It is a guessing game and my suggestion is you pull the pump to verify what it is or get a good Clamp on Ammeter to verify the assumptions. Sorry about my initial mistake.
 
Well, a 19Amp start is consistent with a 5 Amp load to run it but now you are saying 9 Amps to run it? It is a guessing game and my suggestion is you pull the pump to verify what it is or get a good Clamp on Ammeter to verify the assumptions. Sorry about my initial mistake.
I have reached out to the installer and asked him to find his invoice from the manufacturer with the exact model number.
 
Full load amps are your normal running amps, SF amps are slightly overloaded amps, and Surge amps are called Locked rotor amps
The spec sheet has a "Rotor Amps" coluimn but no "Locked Rotor Amps." Same thing?
 
If about 5x the running amps, then yes.

I bought the Harbor Freight $100 1000A AC/DC clamp meter to reach PV string current, battery current, motor starting current. (It has surge feature.)
 
Ok, so I'm an EE but my training is in microelectronics and satellites, so some of this stuff doesn't come naturally to me.

I get split-phase 120V/240V, but I thought 3 phase in the US was considered to be 208V, and assumed it was because of the 120° phase shift between the three lines. I guess I should read up on this...

I guess I'm a little bit skeptical that @forbin actually has a 3 phase 240V well pump. Not many homes have 3-phase at all. It seems more likely that he has a 240V well pump, and the solution is much simpler than we are all making it.
I like this reference: https://ctlsys.com/support/electrical_service_types_and_voltages/
 
I just meant, assuming the inverter has enough power to handle the startup surge and then some, are there any other hurdles to getting something like a split-phase 120V/240V inverter to run a single-phase 240V pump? I am specifically considering the MPP LV6548, which seems like it ought to have enough power with 6.5kW output.
That inverter only outputs 120V, you need two of them for 240V split phase output.
 
Or an auto-transformer (or isolation transformer)
 
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