diy solar

diy solar

3 phase to a 2 Phase Eg4 18kpv Inverter

Pages 39-42 in the EG4 18kPV manual show you two wiring diagrams to handle three phase 208V (if that is what you have).

The first option uses 3x 18kPV (ouch, very expensive)
The second option uses 2x 18 kPV units.

It’s not clear whether you can use just two legs on a single 18kPV.
I would be worried about grid power on L3 being out of phase with the inverter L1,L2 power during the brief time when inverter switches on or off.
If you can ensure that all L3 loads go only to neutral, it might work ok.

You may be looking at buying at least one more 18 kPV
 
Last edited:
You can probably call up EG4 or your retailer and pretend that you are on 120/208 to avoid lawyer defensive clamming up.

To see if it works on two legs with one inverter.

And then take a leap of faith on 127/220
 
I work on 208 often. And I see it coming from the utility around 220. I rarely see 208. It is always higher in my area. If I see 218 on a 208 service, I consider it good.
 
FullNuke said:
we only have 6 mini splits (only cooling); one electric oven and 2 small tankless hot water heater; and a pool motor on timer.
Click to expand...
We need to see what voltage these units are running on and how they are wired up. However those two tankless water heaters are probably going to be your biggest problem.
Yes you might be able to combine two lines together to run from the inverter but you will have to make sure that none of the 220 volt appliances end up minus a line.
If you are trying to offset your cooling bill, you could probably attach all of the mini splits to your inverter and let utility handle the water heaters.
 
FullNuke said:
L1 to L2 = 218
L2 to L3 = 216
L3 to L1 = 218
L1 to N = 127
L2 to N = 126
L3 to N = 126
Click to expand...
The voltages are within reason.
Just need to find out if the 18kpv is OK with connecting to a single phase of a 3 phase WYE system.
Maybe @EG4_Jared can answer this.

You may have to install two.
 
EG4_Jared said:
As far as I can tell from the documentation, 2 inverters would be needed for the 3-phase input. However, I will see what I can find out.
Click to expand...
For 3-phase use, absolutely. It can be done with two or three.
But the question is whether or not it will work on a single phase of a 3-phase system.
I can't imagine that it wouldn't. But confirmation would be appreciated.
 
Batronca - great question; I liked the automatic user interface to be able to do everything on its own as we are not at the home half the year and I jumped the gun without knowing about the two phase. However - what we did was we connected the 18KPV to a two-phase subpanel for the apartment that powers the pool motor and an instant hot water heater.

It is connected to a 50 circuit breaker; 50 from the main panel to the 18KPV and then back to the main panel 50 breaker which is connected to the subpanel in the apartment; maybe in due time we will upgrade to another inverter to make best use of the 3 phase; but at this time I think this is what is best as we can't connect a 3 phase to a single inverter as per Signature Solar.

We have the unit running however going to give Signature Solar a call to commission it and upgrade all the firmwares on Monday.
 
FullNuke said:
Batronca - great question; I liked the automatic user interface to be able to do everything on its own as we are not at the home half the year and I jumped the gun without knowing about the two phase. However - what we did was we connected the 18KPV to a two-phase subpanel for the apartment that powers the pool motor and an instant hot water heater.

It is connected to a 50 circuit breaker; 50 from the main panel to the 18KPV and then back to the main panel 50 breaker which is connected to the subpanel in the apartment; maybe in due time we will upgrade to another inverter to make best use of the 3 phase; but at this time I think this is what is best as we can't connect a 3 phase to a single inverter as per Signature Solar.

We have the unit running however going to give Signature Solar a call to commission it and upgrade all the firmwares on Monday.
Click to expand...
So, it is working fine on the single phase? (You don't have 2 phase)
 
FullNuke said:
Yes I have power to the downstairs unit and it is giving me a reading from the grid. However nothing else has been set up.
Click to expand...
Thanks
Curious to see how it acts when switching between grid and battery.
 
Good morning! So an update - when using the pool motor and the tankless hot water heater simultaneously after about a minute the EG4 KPV stops giving power to the unit to the LOAD. All my breakers are operational in the hot position and the EG4 KPV is still getting power from the utility however it is not giving power to the LOAD. The EG4 PKV breakers are also intact.

Once I reset the breaker from HOT ON to OFF to then HOT ON the EG4 KPV turns on and everything is operational. It stay operational but stops working only when I turn on the pool motor and the TANKLESS hot water heater.

However - there were instances where the EG4 KPV stopped working after a few minutes with only the pool motor working. The notice light is on on the EG4 KPV and I have not done anything with the dip switches or even commissioned it yet. It might be a setting that would need to be done? I am planning on calling Signature Solar to commission the unit on Monday.

Another thing to note is: I turned on everything (3 Mini-Splits and the tankless) the unit worked for 10 minutes no issues; but when I turned on the pool motor it stopped after 2 full minutes. Giving me a feeling of it was a one-off but it wasn't.

Any thoughts? Ideas or is this a commissioning issue that hopefully we can fix with firmware updates and with Signature Solar?
 
FullNuke said:
Any thoughts? Ideas or is this a commissioning issue that hopefully we can fix with firmware updates and with Signature Solar?
Click to expand...
Pool Motor: is this a double pole breaker (220v)?
Tankless Water Heater: is this a double pole breaker (220v)?
Mini splits: are these double pole breakers (220v)?

How many 127v phases are you running through the 18kPV?
One phase + neutral?
Two phases + neutral?
Is the 18kPV in 208/120 mode?
 
You must log in or register to reply here.

Similar threads

J
Need more energy - Multiplus in 3-Phase or Parallel Split-Phase?
Replies
1
Views
255
timselectric
T
natable
3 Phase Microgrid DC Coupled to Grid-Tied Split Phase?
Replies
7
Views
298
Hedges
Hedges
aarongough
EG4 6000XP - 3 phase?
2
Replies
34
Views
2K
Hedges
Hedges
R
Possible to use Sol Ark Gen terminals with a 3 Phase Generator ? Sol Ark techs said NO !
Replies
10
Views
196
Cmiller
C
M
Planing phase - Install DIY 10kw hybrid system
Replies
1
Views
238
mvreddy48
M
Back
Top