looking for big inverter

On 2 Nov 2006 19:06:41 GMT, snipped-for-privacy@ipal.net wrote:


Some examples (not an offer or advertisement, posted only for information): (basically list prices)
XANTREX PV-SERIES LARGE INVERTERS & ACCESSORIES PV "S" Series Inverters (2nd generation PV-series complete w/ DC & AC discos, nite disco, & isolation transformer) Xantrex 100kW, HE, 3-ph 208Vac, LCD display, w/ 208/120vac iso transformer $81,100 Xantrex 100kW, HE 3-ph 208Vac, LCD display, w/ 480/277vac iso transformer $81,100 Xantrex 225kW, 3-ph 208Vac, LCD display, w/ 480/277vac iso transformer $128,846 PV Series Inverters Xantrex 10kW Intertie Inverter, 3-phase 208Vac, LCD display $8,473 Xantrex 15kW Intertie Inverter, 3-phase 208Vac, LCD display $12,220 Xantrex 20kW Intertie Inverter, 3-phase 208Vac, LCD display $15,452 Xantrex 30kW Intertie Inverter, 3-phase 208Vac, LCD display $20,989 Xantrex 45kW Intertie Inverter, 3-phase 208Vac, LCD display $26,647
(Most Grid-Tie Models can not operate without a grid)
BALLARD INTERTIE INVERTERS Grid-Tie Models (MSRP) Ballard Ecostar 480V 75 kW inverter/transformer $61,500 Ballard Ecostar 480V 30 kW inverter/transformer $27,500 Ballard Ecostar 208V 30 kW inverter/transformer $27,500
SATCON LARGE INVERTERS & ACCESSORIES (MSRP) AE-30kW PV Series Inverters SatCon 30kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $30,555 SatCon 30kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $31,275 SatCon 30kW 1-ph 240Vac w/AC & DC discos, iso trans, display & comm port $36,110 Sub-Combiner w/ 3 100A circuits. For 30 or 50 kW SatCon inverters. $509 SatCon 6 to 10 Year Optional Warranty Extension for 30kW 3-ph. $2475 SatCon 11 to 15 Year Optional Warranty Extension for 30kW 3-ph. $4950 SatCon 6 to 10 Year Optional Warranty Extension for 30kW 1-ph. $2925 SatCon 11 to 15 Year Optional Warranty Extension for 30kW 1-ph. $5850
AE-50kW PV Series Inverters SatCon 50kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $35,000 SatCon 50kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $35,910 Internal Sub-Combiner w/ 3 100A circuits. For 30 or 50 kW SatCon inverters. $509
SMA INVERTERS Commercial/Industrial Inverter Sunny Central 125kW Grid-Tie Inverter w/ transformer & discos $63,000
SatCon 6 to 10 Year Optional Warranty Extension for 50kW 3-ph. $2835 SatCon 11 to 15 Year Optional Warranty Extension for 50kW 3-ph. $5670
AE-75kW PV Series Inverters SatCon 75kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $53,000 SatCon 75kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $54,095 Internal Sub-Combiner w/ 6 100A circuits. For 75 or 100 kW SatCon inverters. $955 SatCon 6 to 10 Year Optional Warranty Extension for 75kW 3-ph. $4293 3SC-75A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 75kW 3-ph. $8586
AE-100kW PV Series Inverters 3SC-AE-100-60-A SatCon 100kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $66,000 3SC-AE-100-60-D SatCon 100kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $67,275 3SC-SC6 Internal Sub-Combiner w/ 6 100A circuits. For 75 or 100 kW SatCon inverters. $955 3SC-100A-10YR SatCon 6 to 10 Year Optional Warranty Extension for 100kW 3-ph. $5346 3SC-100A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 100kW 3-ph. $10692
AE-135kW PV Series Inverters 3SC-AE-135-60-A SatCon 135kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $80,000 3SC-AE-135-60-D SatCon 135kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $81,460 3SC-SC9 Internal Sub-Combiner w/ 9 100A circuits. For 135 kW SatCon inverter. $1,435 3SC-135A-10YR SatCon 6 to 10 Year Optional Warranty Extension for 135kW 3-ph. $6480 3SC-135A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 135kW 3-ph. $12960
Bill Kaszeta Photovoltaic Resources Int'l Tempe Arizona USA snipped-for-privacy@pvri-removethis.biz
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On Fri, 03 Nov 2006 03:04:26 GMT Bill Kaszeta / Photovoltaic Resources
| XANTREX PV-SERIES LARGE INVERTERS & ACCESSORIES | PV "S" Series Inverters (2nd generation PV-series complete w/ DC & AC discos, nite disco, & isolation transformer) | Xantrex 100kW, HE, 3-ph 208Vac, LCD display, w/ 208/120vac iso transformer $81,100 | Xantrex 100kW, HE 3-ph 208Vac, LCD display, w/ 480/277vac iso transformer $81,100 | Xantrex 225kW, 3-ph 208Vac, LCD display, w/ 480/277vac iso transformer $128,846 | PV Series Inverters | Xantrex 10kW Intertie Inverter, 3-phase 208Vac, LCD display $8,473 | Xantrex 15kW Intertie Inverter, 3-phase 208Vac, LCD display $12,220 | Xantrex 20kW Intertie Inverter, 3-phase 208Vac, LCD display $15,452 | Xantrex 30kW Intertie Inverter, 3-phase 208Vac, LCD display $20,989 | Xantrex 45kW Intertie Inverter, 3-phase 208Vac, LCD display $26,647
These are 3 phase. I need single phase only.
| (Most Grid-Tie Models can not operate without a grid)
If that were th only issue, I'm sure I could find a way around it, such as supplying some fake grid like power from a smaller inverter.
| BALLARD INTERTIE INVERTERS | Grid-Tie Models (MSRP) | Ballard Ecostar 480V 75 kW inverter/transformer $61,500 | Ballard Ecostar 480V 30 kW inverter/transformer $27,500 | Ballard Ecostar 208V 30 kW inverter/transformer $27,500
Smell like 3 phase to me.
| SATCON LARGE INVERTERS & ACCESSORIES (MSRP) | AE-30kW PV Series Inverters | SatCon 30kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $30,555 | SatCon 30kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $31,275 | SatCon 30kW 1-ph 240Vac w/AC & DC discos, iso trans, display & comm port $36,110 | Sub-Combiner w/ 3 100A circuits. For 30 or 50 kW SatCon inverters. $509 | SatCon 6 to 10 Year Optional Warranty Extension for 30kW 3-ph. $2475 | SatCon 11 to 15 Year Optional Warranty Extension for 30kW 3-ph. $4950 | SatCon 6 to 10 Year Optional Warranty Extension for 30kW 1-ph. $2925 | SatCon 11 to 15 Year Optional Warranty Extension for 30kW 1-ph. $5850
Well, at least there is a single phase one in there. Rather pricy. Maybe it's all the grid-tie certification that adds to that ... plus the tranny.
| AE-50kW PV Series Inverters | SatCon 50kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $35,000 | SatCon 50kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $35,910 | Internal Sub-Combiner w/ 3 100A circuits. For 30 or 50 kW SatCon inverters. $509
More 3 phase.
| SMA INVERTERS | Commercial/Industrial Inverter | Sunny Central 125kW Grid-Tie Inverter w/ transformer & discos $63,000
Scoured their web site last night. Anything over about 3600 watts is grid-intertie at 3 phase.
| SatCon 6 to 10 Year Optional Warranty Extension for 50kW 3-ph. $2835 | SatCon 11 to 15 Year Optional Warranty Extension for 50kW 3-ph. $5670 | | AE-75kW PV Series Inverters | SatCon 75kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $53,000 | SatCon 75kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $54,095 | Internal Sub-Combiner w/ 6 100A circuits. For 75 or 100 kW SatCon inverters. $955 | SatCon 6 to 10 Year Optional Warranty Extension for 75kW 3-ph. $4293 | 3SC-75A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 75kW 3-ph. $8586 | | AE-100kW PV Series Inverters | 3SC-AE-100-60-A SatCon 100kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $66,000 | 3SC-AE-100-60-D SatCon 100kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $67,275 | 3SC-SC6 Internal Sub-Combiner w/ 6 100A circuits. For 75 or 100 kW SatCon inverters. $955 | 3SC-100A-10YR SatCon 6 to 10 Year Optional Warranty Extension for 100kW 3-ph. $5346 | 3SC-100A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 100kW 3-ph. $10692 | | AE-135kW PV Series Inverters | 3SC-AE-135-60-A SatCon 135kW 3-ph 480Vac w/AC & DC discos, iso trans, display & comm port $80,000 | 3SC-AE-135-60-D SatCon 135kW 3-ph 208Vac w/AC & DC discos, iso trans, display & comm port $81,460 | 3SC-SC9 Internal Sub-Combiner w/ 9 100A circuits. For 135 kW SatCon inverter. $1,435 | 3SC-135A-10YR SatCon 6 to 10 Year Optional Warranty Extension for 135kW 3-ph. $6480 | 3SC-135A-15YR SatCon 11 to 15 Year Optional Warranty Extension for 135kW 3-ph. $12960
Tons of 3 phase.
| Bill Kaszeta | Photovoltaic Resources Int'l | Tempe Arizona USA | snipped-for-privacy@pvri-removethis.biz
Much of this endeavor is aimed at being disconnected from the grid/utility. I'm sure solar will be a big part of the system. Wind might be, too. And I'll look for other possibilities such as waterfalls, wood burners, etc. But feeding power back to the utility is just not where I'm going with this at all.
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Using a single system gives a single point of failure.
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| |> Does anyone make a large inverter? I'm exploring the idea of running |> things entirely off-grid. So I'm exploring what all could be done with |> various elements of solar, natural, and renewable power sources to see |> if this might be practical and what constraints it may have when it |> comes time to do this. |> |> But one limitation I have found is that inverters seem to all be on the |> small side and with only limited ability to "stack" them. The largest |> I have seen is 6000 watts. The largest Xantrex model (besides their |> three phase grid tie units) is just 5500 watts. It can be "stacked" |> up to 2 units either parallel (120 volts only) or series (120/240 volts). |> But 11000 watts is a little on the wimpy side and you can't parallel a |> stacked pair. |> |> I could just have multiple systems (probably 2 to 4). But that makes |> more of a wiring nightmare. It would be easier to have a larger inverter. |> And I would be more comfortable with having a single unit that does the |> 3-wire system for 120/240 volts integrated. | | Using a single system gives a single point of failure.
True. So I might also consider redundancy and transfer switching. But the Xantrex 2x5500 was just a bit on the wimpy side. If they offered a 7500 watt model that could be series stacked, that might be good enough. Or if the 5500's could be connected with 4 units in a series + parallel scheme to get 120/240 at 11000 watts, and double that to 22000, that would do, as well. But I've looked at details and it's stacking is very much limited. It has only one stacking cable (I assume is a phase lock control, among other things).
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With used UPS's so plentiful, I would suggest an industrial one. Make sure it can be started from battery while off line.
snipped-for-privacy@ipal.net wrote:

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wrote:
| With used UPS's so plentiful, I would suggest an industrial one. Make | sure it can be started from battery while off line.
That might be an option. But remember, this means tearing the thing apart and connecting the DC to my external battery array. It also means being able to handle a fairly wide DC voltage swing. I'm guessing many of the industrial UPS controllers are going to see a lot of this as a "system problem" and go into shutdown.
I'm not ruling out building my own. And industrial UPSes that get tossed because of dead batteries no one realized could be replaced (I've seen it happen) might be a nice source of parts, at least.
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snipped-for-privacy@ipal.net wrote:

All of the larger UPS that I have seen have had terminals for external batteries. Even ones as small as 1KVA often have them.
However, they aren't designed to take that large a dc voltage swing (other than the usual voltages present on a charging/discharging set of batteries). If the voltage swing takes the level down to the alarm and trip points then, yes, the UPS will act on it.
Another point to watch out for is that inverters, particularly big inverters, normally have chargers that work off the crests of the input supply. They typically need a supply which isn't "squashed", e.g isn't like that produced by many small generators. A 1.5KVA inverter may easily need a 5kVA generator to run the charger at full capacity.
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| snipped-for-privacy@ipal.net wrote:
wrote: |> |> | With used UPS's so plentiful, I would suggest an industrial one. Make |> | sure it can be started from battery while off line. |> |> That might be an option. But remember, this means tearing the thing apart |> and connecting the DC to my external battery array. It also means being |> able to handle a fairly wide DC voltage swing. I'm guessing many of the |> industrial UPS controllers are going to see a lot of this as a "system |> problem" and go into shutdown. |> |> I'm not ruling out building my own. And industrial UPSes that get tossed |> because of dead batteries no one realized could be replaced (I've seen it |> happen) might be a nice source of parts, at least. |> | All of the larger UPS that I have seen have had terminals for external | batteries. Even ones as small as 1KVA often have them.
Generally these are for the battery systems they manufacture and have specified. It's probably not a generic DC input.
| However, they aren't designed to take that large a dc voltage swing | (other than the usual voltages present on a charging/discharging set of | batteries). If the voltage swing takes the level down to the alarm and | trip points then, yes, the UPS will act on it. | | Another point to watch out for is that inverters, particularly big | inverters, normally have chargers that work off the crests of the input | supply. They typically need a supply which isn't "squashed", e.g isn't | like that produced by many small generators. A 1.5KVA inverter may | easily need a 5kVA generator to run the charger at full capacity.
I'd rather have the chargers for any AC sources completely separate.
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snipped-for-privacy@ipal.net wrote:

At these power levels, you really might want to consider a 3-phase distribution system.
The economics of 3 vs single phase is probably what dictates the 5 kW upper end on the latter.
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wrote: | snipped-for-privacy@ipal.net wrote: |> |> Does anyone make a large inverter? I'm exploring the idea of running |> things entirely off-grid. So I'm exploring what all could be done with |> various elements of solar, natural, and renewable power sources to see |> if this might be practical and what constraints it may have when it |> comes time to do this. |> |> But one limitation I have found is that inverters seem to all be on the |> small side and with only limited ability to "stack" them. The largest |> I have seen is 6000 watts. The largest Xantrex model (besides their |> three phase grid tie units) is just 5500 watts. It can be "stacked" |> up to 2 units either parallel (120 volts only) or series (120/240 volts). |> But 11000 watts is a little on the wimpy side and you can't parallel a |> stacked pair. |> |> I could just have multiple systems (probably 2 to 4). But that makes |> more of a wiring nightmare. It would be easier to have a larger inverter. |> And I would be more comfortable with having a single unit that does the |> 3-wire system for 120/240 volts integrated. I have no committment on the |> DC side voltage, but I'd like to be sure it is within the range that can |> be handled by common circuit breakers from Square-D and Cutler-Hammer. |> |> The built-in charger in the Xantrex (and many other) units is also not |> useful. For example, AC power sources might not be able to support the |> peak demand, but I would certainly want to have them supplement batteries |> in those cases. The goal of this is to be off-grid, not as a backup for |> utility outage. |> |> Anyone know of larger single-phase inverters that are in, or can be stacked |> to be in, the 15 to 50 kW range at 120/240 volts? | | At these power levels, you really might want to consider a 3-phase | distribution system. | | The economics of 3 vs single phase is probably what dictates the 5 kW | upper end on the latter.
Which 3 phase configuration would you suggest? Will it give me both 120 volts and 240 volts? (208 volts is not good enough because most things for homes that need more than 120 volts need 240, not 208).
Know of any that are not "grid tie" types?
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snipped-for-privacy@ipal.net wrote:

A previous post had a whole list of them. Most of the 3-phase units are 120/208, but many 120/240V appliances will work on 208.
If what you have is a bunch of smaller loads, you might be better off splitting them up and running a group of smaller inverters. If you really have large individual loads, they will be more efficient running on 3 phase than single phase.

Many of the grid-tie units also operate independently.
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Paul Hovnanian P.E. wrote:

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george snipped-for-privacy@yahoo.com wrote:

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On Sun, 05 Nov 2006 17:11:39 -0800, "Paul Hovnanian P.E."

try MGE s4 line or older s2line.these inverters are standard fare in telcom
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wrote:
| A previous post had a whole list of them. Most of the 3-phase units are | 120/208, but many 120/240V appliances will work on 208.
Many, but not all. I've seen things designed for 240 at best just not work on 208, and at worst burn up.
| If what you have is a bunch of smaller loads, you might be better off | splitting them up and running a group of smaller inverters. If you | really have large individual loads, they will be more efficient running | on 3 phase than single phase.
I am considering the split up. But I don't want to be splitting things up too much. So the goal is each section would be a minimum of 60 amps of 120/240. What I could get out of the Xantrex units is 45 amps.
How does 3 phase make larger loads more efficient? It's a lower voltage.
|> Know of any that are not "grid tie" types? | | Many of the grid-tie units also operate independently.
Now for single phase 120/240 (or series stackable 120).
Or a 6-phase unit.
So, is the real answer that no one makes a single phase 120/240 volt 15kw inverter (just inverter) ... or a 7.5kw series stackable 120 volt one?
All these other ideas might be considered. But right now the quest is to find that elusive inverter that in 1 or 2 units can get me 120/240 volts at 15kw (60 amps).
If I do go with three phase, I'd rather have it producing 480Y/277. Then it's a cheap set of three transformers to step it down to 120/240 in three separate single phase systems ... or a 6 phase system if I tie it all together.
And I might just build my own. Then I can try out a pulse density loop design.
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wrote: | snipped-for-privacy@ipal.net wrote: |>
wrote: |> |> | A previous post had a whole list of them. Most of the 3-phase units are |> | 120/208, but many 120/240V appliances will work on 208. |> |> Many, but not all. I've seen things designed for 240 at best just not |> work on 208, and at worst burn up. |> |> | If what you have is a bunch of smaller loads, you might be better off |> | splitting them up and running a group of smaller inverters. If you |> | really have large individual loads, they will be more efficient running |> | on 3 phase than single phase. |> |> I am considering the split up. But I don't want to be splitting things |> up too much. So the goal is each section would be a minimum of 60 amps |> of 120/240. What I could get out of the Xantrex units is 45 amps. |> |> How does 3 phase make larger loads more efficient? It's a lower voltage. | | Motors, in particular, are more efficient as 3-phase. Easier to start as | well, which should be a consideration when running off an inverter.
Wouldn't that also justify having 3-phase power in all homes. Of course if 3-phase, or 2 lines of it, had been the standard the US used since the early days of electrical service, then all the higher power appliances would be 208 volt instead of 240 volt (unless someone decided to go with 240 delta). But 3-phase is a big hassle because of the different between L-L voltage in that and single phase.
| Other than lots of motor loads, or resistance heat, residences don't | really need that much capacity, particularly at 240V.
Usually, that is true. But sometimes there are peak loads. We have had the stove running full tilt about once or twice a year. If I end up with a lot of free natural energy pickup, and the energy storage is all full, I might as well feel free to use it.
I want to avoid using fossil fuels, so changing the stove/oven over to gas just to avoid electricity isn't the goal. I may still have some gas just because it makes some cooking better. While direct solar water heating can be practical, many other things don't work so well directly fed by the natural energy. Some may work directly fed by DC, such as incandecent lights.
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snipped-for-privacy@ipal.net wrote:

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"Paul Hovnanian P.E." wrote:

(Damned cat jumped on the 'Send' key in mid edit)

Single phase is much cheaper to build for rural electrical distribution systems. Back when energy was cheap and rural customers were happy to get any power, let alone three phase, that's what the utilities built. As load density increases, there is a point where three phase becomes more economic.
I don't know why the difference between line to line and line voltages are a 'hassle' if you design for them. They may be if you are trying to adapt single phase loads to such a system.
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wrote:
| Single phase is much cheaper to build for rural electrical distribution | systems. Back when energy was cheap and rural customers were happy to | get any power, let alone three phase, that's what the utilities built. | As load density increases, there is a point where three phase becomes | more economic. | | I don't know why the difference between line to line and line voltages | are a 'hassle' if you design for them. They may be if you are trying to | adapt single phase loads to such a system.
The problem is, appliances are what have to be designed for the difference in voltage. And that just not done. Many things do work adequately over that differents. But things work less than adequately. Many things just don't work right at all. And even when things do work, new issues occur, such as the 208 volt circuit needs more amps.
If absolutely _everything_ worked on L-N, then that's how standardization should be done. If absolutely _everything_ worked on L-L, then that's how standardization should be done. The problem is we use _both_ L-N and L-L. We need to stick to just ONE of those. And I think L-L is a better choice.
Most of the loads that benefit from L-N are switched lights in screw base sockets. Grounding the outer part of the shell and using only a single pole for the switch is preferred. Additionally, the lower L-N voltage is good for incandescent lights. Given this, that is why I proposed using an even lower voltage (24 or 12) for these lights, and use a higher voltage for the L-L loads (like 240 to 288). L-L at 240 is safer than L-N at 240. We could, of course, go even higher with the L-L voltage.
Would could choose to standardize on single phase (2.000:1 ratio between L-N and L-L) everywhere.
Would could choose to standardize on three phase (1.732:1 ratio between L-N and L-L) everywhere.
Would could choose to standardize on L-N everywhere regardless of phases.
Would could choose to standardize on L-L everywhere regardless of phases.
We instead chose to have a mixed up scheme. At least the Europeans have chosen one of the above.
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