Growatt split phase

[Herbinator]

Growatt 3000 LVM 48v x 2.
Can't get my split phase, dual Growatt 3000s to run at 120v each except in dual single phase. They connect to a split phase, off-grid distribution panel; one to each pole.
When I connect the 2 communication & power cables (rs232?) and set one Growatt to 2P0 and the other to 2P2, they'll correctly display HS and 2P respectively but the output is 0 volts.
- No, they aren't on powersaver.
- Solar only (SOL) charging.
- No faults or warning codes.
- Lithium 100 Ah x 2, fully charged.

It's a conundrum.

 

[Mattb4]

Is that 0vAC between each hot leg at the D panel or from each hot leg to neutral? If it is between each hot leg but you have 120vAC from each hot leg to neutral than you are not set up properly for stacked (split phase) operation. You might however be setup for parallel operation.

 

[Herbinator]

120vAC between each hot and neutral;
a fluttery 120 between the hots (presumably due to uncoordinated sin waves).
Growatt reads 0 vAC output and no power output at the D panel.

 

[Mattb4]

Having never setup a split phase output myself about all I can do is look in the manual and ask if you are wired as shown in this diagram below? In regards to the setting #23 all I can ask is if you made the settings while in Standby mode.

 

[DIYrich]

When I connect the 2 communication & power cables (rs232?)

Connect the two ports on the right (parallel communications). Do not connect the two ports on the left (current sharing port).

 

[Herbinator]

Connect the two ports on the right (parallel communications). Do not connect the two ports on the left (current sharing port).

The diagram shows left connects to right, and right connects to left. I'll check tomorrow if right can connect with right.

 

[Herbinator]

Connect the two ports on the right (parallel communications). Do not connect the two ports on the left (current sharing port).

The cable terminals are M & F so they can't be switched. I did try using only one cable... didn't work, either one.

 

[Mattb4]

You might have a bad parallel communication board.

 

[Herbinator]

I doubt it's a bad board. Changing a parameter on one unit replicates to the other.
And I don't know which machine would have the bad board if there were one.

 

[DIYrich]

The cable terminals are M & F so they can't be switched. I did try using only one cable... didn't work, either one.

Ok. I thought you were trying to use 4 cables: 2 communication cables, and 2 power synch cables, in addition to the battery connections. I think you are supposed to use the 2 communication cables, and no power synch cables.

 

[Herbinator]

Would wiring the Growatts into a breaker on the distribution panel make a difference? They are wired one to each pole, currently.
I don't see that it would make a difference.

 

[jpimlott]

The neutrals need to combined and run to the same load center as the hots.
I have 4 growatts 3k in a split phase setup and works great. The host one needs to on first.
No power sharing cable (green twisted cable) for only 2 growatts. The growatts need to be
connected to the battery though large DC breakers.
Power up would dc power via resistor to precharge caps, power switch on master unit then same procedure
for second unit. Then solar. I user a quad breaker to combine the growatts with each pair going to its own 2 breaker.

 

[240v]

I think you need each inverter on a separate 120v feed for 240v operation. Page 34 2 separate powers and no twisted pairs of wires, just gray cables.

 

[steveg.martin]

Just to add to the conversation, make sure your utility is connected (you should see the electric pole on each inverter) the utility should come from 2 different circuits. Circuit 1 for L1 and inverter 1, and Circuit 2 for L2 for inverter 2.