diy solar

diy solar

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

Yes, but the spec sheet states that it can generate 120 or 240 with only one 1 unit without paralleling. That's a big difference between it and the LV6548.
It has a low-frequency center tap transformer, and is the model I like the best of MPP right now, but it does have higher idle power usage than all the rest of their models, FWIW.
 
It has a low-frequency center tap transformer, and is the model I like the best of MPP right now, but it does have higher idle power usage than all the rest of their models, FWIW.
Idle consumption is a big deal for me right now. Later, when my array is bigger, I won't care as much, but I'm starting with just 3 panels due to space limitations. Idle consumption has the potential to consume 30% of my daily power production. Also, it's hard to string together 3 panels and keep the array Voc high enough to avoid the cutoff when it gets a little overcast. I don't want to waste money on buying a unit now that I'll replace later when I have more panels. So I have quite the challenge: low idle consumption (like 25-30W) low minimum Voc (like 60-90W), 240V split phase without paralleling, 7000W array input power for when I have more panels, and enough output power to run my well pump. It's a tall order. Any ideas?
 
I'm not an expert, but from what I've seen here the AIO's seem to have higher idle consumption than the separate inverter/chargers. My 6 year old Schneider SW4024 has an idle load of only 26W, which is pretty good. The SW4048 (for 48V systems) uses only 27W. Mine's a low freq inverter too, which handles high inrush current loads a bit better than the high frequency inverters.
 
So I have quite the challenge: low idle consumption (like 25-30W) low minimum Voc (like 60-90W), 240V split phase without paralleling, 7000W array input power for when I have more panels, and enough output power to run my well pump. It's a tall order. Any ideas?
Not so big a challenge. Just get a Schneider XWPro and a Midnight controller. It has run my well-pump flawlessly for years now. The XW has an idle consumption of ~30W/hr.

You first need to understand better what you are feeding into your battery bank. A Voc of 60V will NOT work. A Voc of ~60V means the Vmp will be ~48V. 48V will NOT charge a 48V battery!

You really need to slow down here, and do a bit more study and research before you are ready to start making purchases. The worst mistake you can make is going out and buying stuff first, then trying to figure out how to make it work. The way you keep ping-ponging from one idea to the next suggests to me that you don't yet have a clear understanding of what is needed to accomplish what you want.

Please go back to the questions I made in post #13 and please answer those first before going further. I would suggest you STOP using manufacturer specifications which might be for the wrong pump. I would suggest you emperically determine what the numbers are yourself using a clamp meter with "inrush current" capability. Once you have determined the numbers for your pump, then, and only then are you ready to proceed to the design phase.

BTW, I have several clamp meters, including a very expensive Fluke. It doesn't give me numbers different from an far cheaper imported meter called the Uni-T 216C. I suggest you get one before proceeding.
 
I'm not an expert, but from what I've seen here the AIO's seem to have higher idle consumption than the separate inverter/chargers. My 6 year old Schneider SW4024 has an idle load of only 26W, which is pretty good. The SW4048 (for 48V systems) uses only 27W. Mine's a low freq inverter too, which handles high inrush current loads a bit better than the high frequency inverters.
My LV5048 was pretty similar, I measured an idle draw of 25W when only on battery. People are reporting a ~120W idle draw for the LVX6048, which does seem rather excessive. My Growatt 12000t took ~132W, and my Deye 8k takes about 60W.
 
Not so big a challenge. Just get a Schneider XWPro and a Midnight controller. It has run my well-pump flawlessly for years now. The XW has an idle consumption of ~30W/hr.

You first need to understand better what you are feeding into your battery bank. A Voc of 60V will NOT work. A Voc of ~60V means the Vmp will be ~48V. 48V will NOT charge a 48V battery!

You really need to slow down here, and do a bit more study and research before you are ready to start making purchases. The worst mistake you can make is going out and buying stuff first, then trying to figure out how to make it work. The way you keep ping-ponging from one idea to the next suggests to me that you don't yet have a clear understanding of what is needed to accomplish what you want.

Please go back to the questions I made in post #13 and please answer those first before going further. I would suggest you STOP using manufacturer specifications which might be for the wrong pump. I would suggest you emperically determine what the numbers are yourself using a clamp meter with "inrush current" capability. Once you have determined the numbers for your pump, then, and only then are you ready to proceed to the design phase.

BTW, I have several clamp meters, including a very expensive Fluke. It doesn't give me numbers different from an far cheaper imported meter called the Uni-T 216C. I suggest you get one before proceeding.
I know it is a PenTek XE Series 1HP pump. The manufacturer only makes 6 different models of XE Series Single-Phase 1 HP pumps. 4 of them show Locked Rotor Amps of 41A. The other two show 21A and 24A respectively. My cheap Meterk clamp meter does not measure inrush amps, but I measured running amps at 7A. The typical rule of thumb is that inrush amps should be 3-5 times running amps, which would put it at 21-35A. That means I probably have the PenTek P42B0010A2, which is listed at 21.7 inrush amps. However, just to be safe, I'll use the highest number on the spec sheet and assume the inrush is 42A, which works out to ~10,000 W. So it seems that an inverter that can handle 10,000 W for a few seconds once a week should do the trick.

Oh, and I forgot to mention one other data point in my challenge. I want to do it with equipment from MPP, Growatt, EG4, or another vendor of similar quality. I cannot afford Schneider, Sol-Ark, or the other big boys who are, shall we say, very proud of their equipment. No doubt they have great reasons for their pricing, but their reasons do not put extra money in my bank account.
 
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No doubt they have great reasons for their pricing, but their reasons do not put extra money in my bank account.
I would guess one of the,"reasons " is the cost of. UL listing which, I agree, does not put money in your bank account but for some, makes permitting easier.
 
I think it’s worth it to grab a meter that can record the actual inrush current because that will narrow down what inverter to get.
 
However, just to be safe, I'll use the highest number on the spec sheet and assume the inrush is 42A, which works out to ~10,000 W. So it seems that an inverter that can handle 10,000 W for a few seconds once a week should do the trick.

Oh, and I forgot to mention one other data point in my challenge. I want to do it with equipment from MPP, Growatt, EG4, or another vendor of similar quality. I cannot afford Schneider, Sol-Ark, or the other big boys who are, shall we say, very proud of their equipment.

You appear to be wholely absorbed with pen and paper documentation rather than empirical testing. It seems you won't accept suggestions like getting an "inrush current" meter, either because you are very cheap, or very inexperienced. In either case, to be frankly honest, this mentality will guarranty your failure. There is an order of magnitude difference between powering your TV via solar, and powering your well-pump via solar. You need quality equipment to get that done.

You will end up spending more money. Once for the MPP, and again for an inverter that actually works. At this point all I can say is "you'll find out". I really hope you don't end up burning out your well-pump, because replacing one is nothing to look forward to.
 
You appear to be wholely absorbed with pen and paper documentation rather than empirical testing. It seems you won't accept suggestions like getting an "inrush current" meter, either because you are very cheap, or very inexperienced.
I'm inexperienced, for sure, and certainly cheap, but neither of those are factors in this case. I live in the wilderness, 30 minutes from the nearest paved road and about 1.5 hours from a Home Depot. I leave the mountain about once every 1-2 weeks. The thread was getting old, so I provided at least some empirical information. It sounds like you believe there's a chance my particular model of PenTek pump has an inrush current that is more than 6 times its running load, which would be pretty unusual, from what I've been told, and could mean the pump is drawing up to 150% more than the manufacturer's published LRA spec. I sure hope that's not the case, but I'll confirm with a better clamp-meter when I can.
 
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Surge of 5x rated power is what I expect, and have measured for one or two motors. Sometimes running current below spec.
When a motor has a starting winding, either switched (common for some applications) or through a start/run capacitor (typically for higher torque), maybe it draws additional current beyond what 5x rated would indicate.

In 3-phase applications, LRA is a similarly higher value, and that's just the running windings.

Growatt 5kW rated 2x surge power for 5 seconds, in manual but not spec sheet.

 
Do you happen to know of an inexpensive ammeter that can record a valid peak amps value @Hedges ? I have a few clamp meters but none of them can capture the peak. There seems to be a lot that list that as a feature, but I don't want to just buy shots in the dark, myself.

It appears watts247 is going to firesale the next shipment of Growatt 5000 ES, if you are okay dealing with removing the screw yourself @forbin
https://watts247.com/product/spf-5000-es/
 
I live in the wilderness, 30 minutes from the nearest paved road and about 1.5 hours from a Home Depot. I leave the mountain about once every 1-2 weeks.
My place is 60 minutes up a dirt mountain road, twice as far, but I somehow managed to do all the background investigation I mentioned, and installed a quality inverter myself.
It sounds like you believe there's a chance my particular model of PenTek pump has an inrush current that is more than 6 times its running load, which would be pretty unusual, from what I've been told, and could mean the pump is drawing up to 150% more than the manufacturer's published LRA spec. I sure hope that's not the case, but I'll confirm with a better clamp-meter when I can.
I'm pretty sure I've NEVER mentioned "6 times" to anyone here. In my own case, testing my own pump, I find it runs on 9.5A, but has an inrush of 38A, when ends up being 4X. That is the number I almost always quote when talking about starting surge.

The critical point I'm trying to make is that you shouldn't be asking what the starting surge is, you should be determining what the starting surge is. My concern is if you are not up to that level of expertise, then you really aren't at the level of doing this yourself.
Do you happen to know of an inexpensive ammeter that can record a valid peak amps value @Hedges ? I have a few clamp meters but none of them can capture the peak. There seems to be a lot that list that as a feature, but I don't want to just buy shots in the dark, myself.
I have this one, that has worked well for me. Prices are going up though. I think I got my first one for 58$. I also have a far more expensive Fluke meter with inrush capability, but I find that when used side by side, the UniT matches to within 1% accuracy.
 
My place is 60 minutes up a dirt mountain road, twice as far, but I somehow managed to do all the background investigation I mentioned, and installed a quality inverter myself.

I'm pretty sure I've NEVER mentioned "6 times" to anyone here. In my own case, testing my own pump, I find it runs on 9.5A, but has an inrush of 38A, when ends up being 4X. That is the number I almost always quote when talking about starting surge.

The critical point I'm trying to make is that you shouldn't be asking what the starting surge is, you should be determining what the starting surge is. My concern is if you are not up to that level of expertise, then you really aren't at the level of doing this yourself.

I have this one, that has worked well for me. Prices are going up though. I think I got my first one for 58$. I also have a far more expensive Fluke meter with inrush capability, but I find that when used side by side, the UniT matches to within 1% accuracy.
It sounds like you have a great place and I'm not trying to compete with you. I was explaining why I have not had an opportunity to get a better clamp meter in the few days between your original comment and yesterday. Despite the fact that I initially said I was about ready to purchase something, I'm still gathering information. I joined the SolarPanelTalk forum 7 years ago back in 2015 and I've been reading and researching intermittently since then, but only in the past year have I been getting serious, and in the past few months really serious, but I know there is a lot to learn and everyone has to start somewhere.

You did not say anything about "6 times." That's just what the math seems to work out to. I believe I have a PenTek P42B0010A2 pump, which is listed at 21.7 LRA. Since I have not yet confirmed it, I'm assuming for conversational purposes that I have PenTek's highest powered 1HP model, which is listed at 42A LRA. I know, based on testing, that my pump draws 7A when running. If its inrush power is more than 42A, then it would be using more than 6 times it's running Amps, which is uncommon. That's what I was trying to communicate. I get the critical point you are trying to make.
 
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I get the critical point you are trying to make.
Sorry, I just get so intense! Will try to relax a bit. I try to convey that good solar isn't cheap, and cheap solar isn't good. If you are trying to go off-grid to save money, you are making a mistake. A lot of people miss that completely. I try to advise people on what I know works. That's why I try to push people in a certain direction.
 
Sorry, I just get so intense! Will try to relax a bit. I try to convey that good solar isn't cheap, and cheap solar isn't good. If you are trying to go off-grid to save money, you are making a mistake. A lot of people miss that completely. I try to advise people on what I know works. That's why I try to push people in a certain direction.
No worries. We've been living 100% off grid for a little over two years. The cabin came with a small 12V solar system and I've been learning some things in the process of using and tending to it. I've had to replace the charge controller twice, the inverter twice, the battery chargers, and re-wire the circuit breaker box, and re-route the panel wires, and replace fuses and cutoffs, and so forth, and install a whole new battery bank. In fact, the only part of the system that I haven't replaced are the panels. Thankfully, 12V is fairly safe for beginners. Our appliances are all propane and the daily water supply comes from a 500 gal. tank that feeds the house through an RV pump. We have no A/C, so our power consumption is low, around 4kWh per day, and a big chunk of that is the inverter's idle consumption. Even so, we end up running the generator way too much. I killed my bank of FLA batteries through abuse and neglect. Lesson learned. Now I want to get a more powerful system that can run more things and give us a few days of autonomy, and I'm trying to fit a lot of priorities into a small space and a small budget. My progress toward a final design is glacial.
 
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