Parallel 3*8kw Sunsynk for 3P

[Dinz]

Hi Forumites

I have 3 Sunsynk 8Kw inverters to make up a 3 phase system.

I struggle to get them to communicate with each other.

I'm not sure what I'm doing wrong.

 

I've set up so far:

1. All 3 are on latest and same version.

2. All 3 are masters of their own phase. (Phase A/B/C).

3. Phase A set as Master with Modbus 01, Phase B set as Master with Modbus 02, Phase C Set as Master with Modbus 03.

4. Battery bank comms connected to Phase A Modbus 1.

5. Parallel ticked off on all 3

6. Straight ethernet cable between all 3

7. Dip Sw ON, on all 3.

 

Getting F41 error.

Not sure what I've done wrong.

Should the other 2 inverters be set as slaves maybe?

Dip Sw should be off on first 2 inverters?

 

 

Thanks!

 

 

 

[macafrican]

In three phases, should the systems be set up as parallel at all?

[Dinz]

This is what I've followed from the manual.

 

 

Is it wrong probably?

 

[TaliaB]

48 minutes ago, Dinz said:

Hi Forumites

I have 3 Sunsynk 8Kw inverters to make up a 3 phase system.

I struggle to get them to communicate with each other.

I'm not sure what I'm doing wrong.

 

I've set up so far:

1. All 3 are on latest and same version.

2. All 3 are masters of their own phase. (Phase A/B/C).

3. Phase A set as Master with Modbus 01, Phase B set as Master with Modbus 02, Phase C Set as Master with Modbus 03.

4. Battery bank comms connected to Phase A Modbus 1.

5. Parallel ticked off on all 3

6. Straight ethernet cable between all 3

7. Dip Sw ON, on all 3.

 

Getting F41 error.

Not sure what I've done wrong.

Should the other 2 inverters be set as slaves maybe?

Dip Sw should be off on first 2 inverters?

 

 

Thanks!

 

 

 

I think the question i want to ask are you using 3 x Sunsynk 8kw single phase inverters and you are trying to create a three phase system for 3 ph loads? Do you have 3ph 4 wire or single phase Eskom supply to your premises. The error you are getting F41 - Parallel System Stop - Error

[abd7]

1 hour ago, Dinz said:

Hi Forumites

I have 3 Sunsynk 8Kw inverters to make up a 3 phase system.

I struggle to get them to communicate with each other.

I'm not sure what I'm doing wrong.

 

I've set up so far:

1. All 3 are on latest and same version.

2. All 3 are masters of their own phase. (Phase A/B/C).

3. Phase A set as Master with Modbus 01, Phase B set as Master with Modbus 02, Phase C Set as Master with Modbus 03.

4. Battery bank comms connected to Phase A Modbus 1.

5. Parallel ticked off on all 3

6. Straight ethernet cable between all 3

7. Dip Sw ON, on all 3.

 

Getting F41 error.

Not sure what I've done wrong.

Should the other 2 inverters be set as slaves maybe?

Dip Sw should be off on first 2 inverters?

 

 

Thanks!

 

 

 

With this setup parallel needs to be ticked. That's how the other inverters will know to recieve BMS info from the one where the BMS is connected to. 

So each will be set as master, different modbus and phases as currently done, but parallel needs to be ticked on all . 

[abd7]

39 minutes ago, Dinz said:

This is what I've followed from the manual.

 

 

Is it wrong probably?

 

As you can see there parallel is ticked. 

[Dinz]

1 hour ago, TaliaB said:

I think the question i want to ask are you using 3 x Sunsynk 8kw single phase inverters and you are trying to create a three phase system for 3 ph loads? Do you have 3ph 4 wire or single phase Eskom supply to your premises. The error you are getting F41 - Parallel System Stop - Error

Yes I am using 3 single phase inverters. I have 3 phase supply from Eskom, and each phase goes to a seperate inverter. I want to output 3 phase also. I am getting F41 error. 

 

Thanks

[Steve87]

Switch the dip switches off on all 3...you have no slaves in each phase. They are all masters on the respective phase. The Dip switch is a means for a master to know where the last slave lies. In this case there are no slaves. 

Also makes 100% sure to use Quality Shielded Cat 5e utp cable. The other non shielded cables can allow noise through. 

[TaliaB]

44 minutes ago, Dinz said:

Yes I am using 3 single phase inverters. I have 3 phase supply from Eskom, and each phase goes to a seperate inverter. I want to output 3 phase also. I am getting F41 error. 

 

Thanks

I have never tried this. If the supply is 3ph i parallel 3ph inverters if the supply is single phase i parallel single phase inverters. I stand to be corrected maybe the Sunsynk can do this. 

For 3-phase power you need a source that maintains a 120 degree phase angle between the 3 line outputs. A 3-phase inverter will generate all 3 phases from a single clock source, and keep the phases separated properly in phase.

A single-phase inverter (unless it is designed to be part of a 3-phase inverter) isn’t going to have an input for it to phase-lock its output to. Each of the three “identical” inverters will have its own internal crystal as the reference for its 50 Hz output, but the crystals will be slightly different in frequency. So even if you could get the 3 inverters to be 120 degrees apart when you start up, they won’t stay 120 degrees apart.

Maybe @BritishRacingGreencan weigh in if this would be possible to do with the Sunsynk 1ph inverters.

[TaliaB]

5 minutes ago, Steve87 said:

Switch the dip switches off on all 3...you have no slaves in each phase. They are all masters on the respective phase. The Dip switch is a means for a master to know where the last slave lies. In this case there are no slaves. 

Also makes 100% sure to use Quality Shielded Cat 5e utp cable. The other non shielded cables can allow noise through. 

Hi @Steve87 so you most probably did it and it works on the 3 x Sunsynk single phase to Eskom 3ph supply jolly good so we learn new stuff everyday. 

 

[Steve87]

@TaliaBthe Sunsynk as well as even the Humble Kodak Voltronics machines can create 3 phase power with 3 single phase inverters. They have firmware that sorts out the 120° split of the phases. However, they need a means to Synchronize to & they receive this from the Grid AC input then follow along happily. 

I think the Dip switches should sort the Parallel issues out here & true 3 phase power will be generated...

But the yellow Sunsynk cables they provide are very poor quality & are not shielded but are twisted pairs. But there is so many noise sources that can spoil the day that I always try to replace those cables. They are just not up fro the challenge. The Inverters communicate via Canbus Comms & that needs Twisted & shielded cable as a prerequisite. 

[BritishRacingGreen]

3 hours ago, TaliaB said:

I have never tried this. If the supply is 3ph i parallel 3ph inverters if the supply is single phase i parallel single phase inverters. I stand to be corrected maybe the Sunsynk can do this. 

For 3-phase power you need a source that maintains a 120 degree phase angle between the 3 line outputs. A 3-phase inverter will generate all 3 phases from a single clock source, and keep the phases separated properly in phase.

A single-phase inverter (unless it is designed to be part of a 3-phase inverter) isn’t going to have an input for it to phase-lock its output to. Each of the three “identical” inverters will have its own internal crystal as the reference for its 50 Hz output, but the crystals will be slightly different in frequency. So even if you could get the 3 inverters to be 120 degrees apart when you start up, they won’t stay 120 degrees apart.

Maybe @BritishRacingGreencan weigh in if this would be possible to do with the Sunsynk 1ph inverters.

Correct what you stating there , and , yes, @Steve87 has confirmed that for SunSynk and MKS/MAX style Axperts , you can configure individual machines for true 3-phase functionality. Sharing of PV power amongst the three becomes a bit of a challenge when the load priority is Solar-Utility- Battery . But in Solar-Battery-Grid mode the sharing is excellent . Any phase that has extra PV power , over and above its own needs,  will make it available on the common battery bus , and the other machines will 'skim' this 'fat' off the battery bus , without any power flowing into or out of the battery itself.! An example of how powerful and simplistic  the way DC blending works.

 

Edited September 3 by BritishRacingGreen

[Dinz]

Hi Everyone.

 

So just an update and some responses to the above.

 

The setup is working.

It is as follows:

I have 3ph Grid supply.

 

I've used 3 8Kw Single phase SS Inverters

I have 6 5Kw Pylontec batteries in a bank.

21 550W panels split between the inverters

Each phase of of Grid goes to a seperate inverter input.

Each inverter output is a seperate phase, obviously.

 

Multi Inverter setting - All 3 are Masters and  each have been assigned Phase A, Phase B and Phase C respectively.

All 3 Inverters are connected to the battery bank.

 

Phase A inverter is controlling or communicating with the battery bank as it has the CAN cable connected to it.

 

2 Things happened to make it work -

SS done an update. I thought I had the latest, but I was one behind on all of them. (6.0.2.6).

Full system power down and restart.

 

 

Hope this helps anyone out there. I can share details if anyone wants to run this sort of setup.

 

System is just as this diagram in the manual:

 

[JayMardern]

21 hours ago, BritishRacingGreen said:

Any phase that has extra PV power , over and above its own needs,  will make it available on the common battery bus , and the other machines will 'skim' this 'fat' off the battery bus , without any power flowing into or out of the battery itself.! An example of how powerful and simplistic  the way DC blending works.

It's fascinating (and I found this initially a bit confusing) - as this happens also in single-phase parallel setups (at least in the case of the my 2 paralleled single-phase 5kW Sunsynks), and is part of the reason why it's important to have both inverters under the same Plant,

Because even in single-phase, the AC load (UPS + Aux + Zero-Export-to-Grid) being served the system is always split evenly between the inverters, and if one is producing less PV than the other,  the DC-transfer-via-battery-bus you describe is used to satisfy the under-performing unit.

So let's say you have a 4kW AC load being served by two inverters with their own arrays - and one array is producing 3kW and the other is producing 1kW (say, due to shading). Both inverters are always going to contribute 2kW each for the total 4kW AC load - but the PV is indeed skimmed off the one array to the other (from one inverter to the other). And when this happens, the 3kW-PV-producing inverter will report a 'Battery Charge' of 1kW, and the 1kW-PV-producing inverter will report a 'Battery Discharge' of 1kW (for a nett charge/discharge of 0kW between the two) to allow the excess PV from the one inverter to be used by the other.

And of course in this case, the LiBMS screen will report 0A charge since no current is actually entering the battery.

By putting both inverters under the same plant, the plant totals are still correct because the they're 'added' together in the app/website which gives the true battery charge values.

 

51 minutes ago, Dinz said:

So just an update and some responses to the above.

The setup is working.

2 Things happened to make it work -

SS done an update. I thought I had the latest, but I was one behind on all of them. (6.0.2.6).

Full system power down and restart.

Hope this helps anyone out there. I can share details if anyone wants to run this sort of setup.

 

Good to hear you're sorted and thanks for sharing your experiences with us.

 

[macafrican]

By the way, not sure if your supplier allows exporting solar, but if you do, I am 99% certain using three single phase inverters is not allowed.   NRS requires you to export equally across three phases.    I’m not sure why they require this, as it “costs” power.    Eg if you have three phase grid tied inverter of 9kW and at the time when you have 9kW solar you have loads of 1 and 1 and 2, you can’t export 5kW - you can only export 1+1+1