3 phase solar

[snowmaneu1]

If the OP connected 3 inverters with a common connection and then has 3 legs hot, he has it configured in a "wye" configuration.

Currently he must have the output of each inverter set to 208V. This would create a system of 208V L-N and 360V L-L.

In order to get 240V L-L, he needs the output set to 138.7V in a "wye" configuration ( this output is not possible with this inverter)

Set the Inverter to 208V output, L-L config and get 2 - 32V secondary, "boost" transformers, wired in an open delta, to boost from 208 to 240 ( *** edit: I just remembered that these inverters cannot be set to 120V. In that case you are SOL )

When I set each inverter in the three phase setup to 208v, I get 208v l-n and 360 L-L. These are 48 v inverters.

 

[mike93lx]

Is the well pump the only 3 phase equipment? What is its HP rating?

 

[snowmaneu1]

are the growatts PWM "pure sine" or multi-tap transformer pure sine inverters?
360V sounds like DC bus voltage on a VFD fed with 230-240V. many multi-meters have issue reading RMS voltage on PWM outputs, especially with zero load.

i guess you could wire some 230V light bulbs up and see if they go POP!

Are you suggesting the growatt 3 phase system might be able to supply appropriate power to 230v light bulbs without blowing them because my multimeter may be insufficient to read the correct voltage being produced at 3 phase growatt source ?

 

[u3b3rg33k]

Pure sine wave

but which "pure" sine wave?

unless it's an audio amplifier running at "i don't care" efficiencies, you didn't answer the question.

 

[u3b3rg33k]

Are you suggesting the growatt 3 phase system might be able to supply appropriate power to 230v light bulbs without blowing them because my multimeter may be insufficient to read the correct voltage being produced at 3 phase growatt source ?

I'm saying if you blow the light bulbs you know it ain't 230v

I've got a "phase tester" at work made of 3x 230V lightbulbs wired in delta, because some of our production switching equipment (uses SSRs) can't be tested with a high impedance multi-meter. you need a real load to know for sure if they're "on".

 

[snowmaneu1]

Is the well pump the only 3 phase equipment? What is its HP rating?

It is .. Franklin electric Franklin Electric 2347178602G, 4" Submersible Well Motor, 230 Volts, 5 HP, 60 Hz, 15.9 Amps, 3 Wire, 3 Phase, 3450 RPM, Motor Lead

 

[snowmaneu1]

but which "pure" sine wave?

unless it's an audio amplifier running at "i don't care" efficiencies, you didn't answer the question.

I'll find out .I .didnt know the nuances of pure since wave varieties

 

[American Locomotive]

Exactly..but I'll forgo the grid tie.. as long as I can get the 3 phase 400 down to 3 phase 240

I really, really recommend returning these inverters and getting something else that can actually do 120/208 or 240v 3-phase. Yes, you can probably use a transformer, but you're adding a lot of cost.

You're probably looking at $1500-2000 for a 400v>208/230 step-down transformer.

 

[mike93lx]

It is .. Franklin electric Franklin Electric 2347178602G, 4" Submersible Well Motor, 230 Volts, 5 HP, 60 Hz, 15.9 Amps, 3 Wire, 3 Phase, 3450 RPM, Motor Lead

I wonder if all this complexity is worth it for a single 5hp motor

 

[snowmaneu1]

Is the well pump the only 3 phase equipment? What is its HP rating?

It is 5 hp , but the existing delta utility also runs an additional 120,120,208 3 phase group of wiring (with its utility neutral) to a building on site 200 yards away. I'd like to mimick it's phase so the solar inverters can power that building .. nothing in that building is three phase. The electrical panel uses 240 double pole breakers, as well as 120v single pole breakers ..

 

[snowmaneu1]

I wonder if all this complexity is worth it for a single 5hp motor

Well.. I just replaced the well pump and paraphernalia for 12,000 so I'm wanting to deal with it

 

[snowmaneu1]

I really, really recommend returning these inverters and getting something else that can actually do 120/208 or 240v 3-phase. Yes, you can probably use a transformer, but you're adding a lot of cost.

You're probably looking at $1500-2000 for a 400v>208/230 step-down transformer.

Thanks .. ya that's what I was figuring for cost as well

 

[mike93lx]

Well.. I just replaced the well pump and paraphernalia for 12,000 so I'm wanting to deal with it

Holy ****. Yeah, I would imagine so

 

[snowmaneu1]

I'm saying if you blow the light bulbs you know it ain't 230v

I've got a "phase tester" at work made of 3x 230V lightbulbs wired in delta, because some of our production switching equipment (uses SSRs) can't be tested with a high impedance multi-meter. you need a real load to know for sure if they're "on".

Thanks

 

[wyliesdiesels]

If the OP connected 3 inverters with a common connection and then has 3 legs hot, he has it configured in a "wye" configuration.

Currently he must have the output of each inverter set to 208V. This would create a system of 208V L-N and 360V L-L.

In order to get 240V L-L, he needs the output set to 138.7V in a "wye" configuration ( this output is not possible with this inverter)

Set the Inverter to 208V output, L-L config and get 2 - 32V secondary, "boost" transformers, wired in an open delta, to boost from 208 to 240 ( *** edit: I just remembered that these inverters cannot be set to 120V. In that case you are SOL )

yup and he cant connect them to a 3-wire 240v delta in that config...

 

[wyliesdiesels]

It is 5 hp , but the existing delta utility also runs an additional 120,120,208 3 phase group of wiring (with its utility neutral) to a building on site 200 yards away. I'd like to mimick it's phase so the solar inverters can power that building .. nothing in that building is three phase. The electrical panel uses 240 double pole breakers, as well as 120v single pole breakers ..

and those breakers need to be straight rated 240v due to the 208v to ground on the hi-leg

 

[Steve from Socal]

There is another way to run the pump,

Get you inverters to 380~400 volts and use a VFD inverter to power the pump at its normal voltage/Hz

 

[wyliesdiesels]

There is another way to run the pump,

Get you inverters to 380~400 volts and use a VFD inverter to power the pump at its normal voltage/Hz

but IIRC he wants this to be grid tied so that wont work... Also a VFD designed to work on US voltages isnt gonna like the oddball voltage input.

 

[wyliesdiesels]

Well.. I just replaced the well pump and paraphernalia for 12,000 so I'm wanting to deal with it

best thing to do here is get the right inverters

 

[snowmaneu1]

but IIRC he wants this to be grid tied so that wont work... Also a VFD designed to work on US voltages isnt gonna like the oddball voltage input.

Not ideal but, I can have a 48v charger run off delta 240 plug and set to kick in at 52vdc to charge batteries direct .. "isn't going to like" meaning what .. it'll blow up ??

 

[snowmaneu1]

There is another way to run the pump,

Get you inverters to 380~400 volts and use a VFD inverter to power the pump at its normal voltage/Hz

So that means?? .. three hots 400 go into the VFD which steps it down ?? And three hots come out at 240 .. suggestions for a make and model manufacturer brand

 

[snowmaneu1]

and those breakers need to be straight rated 240v due to the 208v to ground on the hi-leg

What does straight rated 240 mean ?

 

[PCustoms]

What does straight rated 240 mean ?

Jesus you're so far over you're head you don't even know

 

[inphx]

There might be some clarification needed regarding 'grid-tied' as well. Are we referring to grid input into the inverter as an alternative source, like a backup to solar power? Or are we talking about a true grid-tied system that's approved by the power company (POCO) to feed electricity back into the grid?

 

[dcg9381]

There might be some clarification needed regarding 'grid-tied' as well. Are we referring to grid input into the inverter as an alternative source, like a backup to solar power? Or are we talking about a true grid-tied system that's approved by the power company (POCO) to feed electricity back into the grid?

This is a good point. There is "power source" (battery charge source) from the gird that does not need to be sync'd up.
Grid tie to me means that I'm potentially pushing power back to the grid... Different ball of wax.

I've never seen this sort of power setup before... Must be a CA or "industrial power" thing?

 

[wyliesdiesels]

What does straight rated 240 mean ?

most residential breakers are slash [/] rated meaning for a line to line short they handle 240v and for line to ground fault they handle 120v. straight rated means for any fault they handle 240v. This is needed for delta services because they have the hi-leg (208v to ground), which will have higher fault energy.

 

[Steve from Socal]

but IIRC he wants this to be grid tied so that wont work... Also a VFD designed to work on US voltages isnt gonna like the oddball voltage input.

So that means?? .. three hots 400 go into the VFD which steps it down ?? And three hots come out at 240 .. suggestions for a make and model manufacturer brand

The suggestion I made was based on the pump being THE issue. I have some ABB 480 volt inverters that are built to work at 380-480 50/60Hz input. These are not small comodity type inverter/VFD's

That could solve the pump issue. The whole battery bank would then be at 380~400 volts like European voltage but 60Hz. That is as Wylie noted an odd voltage/Hz The suggestion to get the correct inverters is really the way to fix this.

I would even question why you 'need' a three phase system. If the pump is the only three phase device on the system a single phase input VFD could power the pump.

 

[wyliesdiesels]

I've never seen this sort of power setup before... Must be a CA or "industrial power" thing?

im in Cali. never seen it before either.... im not really even sure what the OP is trying to accomplish other than maybe run a pump on solar and batteries which unless the pump is minimal use, probably wont run very long... he did mention he has grid tie capability via some disconnects if i understood correctly.

im wondering how any of this got AHJ and PoCo approval

 

[Norcal]

im in Cali. never seen it before either.... im not really even sure what the OP is trying to accomplish other than maybe run a pump on solar and batteries which unless the pump is minimal use, probably wont run very long... he did mention he has grid tie capability via some disconnects if i understood correctly.

im wondering how any of this got AHJ and PoCo approval

May be bootleg solar.

 

[wyliesdiesels]

gonna be magic smoke solar if he closes that disconnect

 

[u3b3rg33k]

gonna be magic smoke solar if he closes that disconnect

yeah - if it's operating as a grid-tie, output should have 0V until it picks up the grid signal to sync to.

otherwise it would need to be its own panel.

QO-H breakers (commonly found on grounded-B systems)

What is the difference between the QOB and QOB-H circuit breaker? | Schneider Electric USA

www.se.com

IIRC QO-H breakers do not exist in single pole.

 

[snowmaneu1]

Jesus you're so far over you're head you don't even know

Thanks

 

[snowmaneu1]

There might be some clarification needed regarding 'grid-tied' as well. Are we referring to grid input into the inverter as an alternative source, like a backup to solar power? Or are we talking about a true grid-tied system that's approved by the power company (POCO) to feed electricity back into the grid?

Backup to solar and battery..not FED back to the grid

 

[snowmaneu1]

There is another way to run the pump,

Get you inverters to 380~400 volts and use a VFD inverter to power the pump at its normal voltage/Hz

So you're saying ..take them out of three phase .. place them all on the same phase .. then use a VFD to create the third hot ?

 

[dcg9381]

Backup to solar and battery..not FED back to the grid

And not fed from the grid at all?

Why the heck would you try to do this the 3-phase way (other than having that existing pump)? You're already in for 3 inverters + a new panel... I'd be replacing that pump with single phase 240V pump, single inverter, etc.

 

[Steve from Socal]

So you're saying ..take them out of three phase .. place them all on the same phase .. then use a VFD to create the third hot ?

What voltage/Hz do these have in single phase. If they can produce 240/60 or 208/60 you could use one to power a VFD to generate three phase for the pump. That still leaves you with an issue to either transform that voltage to 120 or some other inverters to provide 120 service.

The inverters you have are for European standards? The voltage/frequency is never going to work with 120 volt north American standards

 

[wyliesdiesels]

There is no point in trying to get these to work with your current pump since they are European voltages and your pump is US voltage

What is the reason in wanting to use solar and batteries to run the pump instead of just using your existing Delta service to run it?

 

[snowmaneu1]

May be bootleg solar.

I only want to use grid to supply power to AC in when solar or batteries cant meet load demands. The UNITS have that capacity. I am not feeding back to grid
These inverters are sold through signature solar as it's first USA distributor and are ul 1701

What voltage/Hz do these have in single phase. If they can produce 240/60 or 208/60 you could use one to power a VFD to generate three phase for the pump. That still leaves you with an issue to either transform that voltage to 120 or some other inverters to provide 120 service.

The inverters you have are for European standards? The voltage/frequency is never going to work with 120 volt north American standards

They operate at a user selected 50 or 60 Hz. Single phase they have two hots and a ground. The pump motor is 120,120,208 delta 240v Well the manufacturer said it's been configured for both markets. Just doesn't do 240v out in 3 phase . It will in single phase. Ive run a few 240v motors off a single inverter . These are ul 1741. Its not designed to do 120 though ..just 240 .

 

[snowmaneu1]

There is no point in trying to get these to work with your current pump since they are European voltages and your pump is US voltage

What is the reason in wanting to use solar and batteries to run the pump instead of just using your existing Delta service to run it?

Grid independance

 

[snowmaneu1]

I only want to use grid to supply power to AC in when solar or batteries cant meet load demands. The UNITS have that capacity. I am not feeding back to grid
These inverters are sold through signature solar as it's first USA distributor and are ul 1701

They operate at a user selected 50 or 60 Hz. Single phase they have two hots and a ground. The pump motor is 120,120,208 delta 240v Well the manufacturer said it's been configured for both markets. Just doesn't do 240v out in 3 phase . It will in single phase. Ive run a few 240v motors off a single inverter . These are ul 1741. Its not designed to do 120 though ..just 240 .

Meant ul 1741