Hi guys

Got a new Sunsynk 5kW installed with zero pv panels yet and a 5.1kW locally produced Navitas lifpo4 wall mounted batt. 2/5 times when AC returns after loadshitting the inverter drops the normal light and power goes down in my home. No fault code logged. Within 60sec it resets itself and reconnects. I have  tried to play with the settings - reduced reconnect time to 10s, upped and downed the trip frequency and voltages etc. Also set charge current to 40A and discharge current to 90A

I also have the NE bonding relay installed and Islanding mode active. It works as intended. I fed the inverter from a 40A DP circuit breaker.

Not sure if this is a inverter fault perhaps or what?

Thanks

Edited April 21, 20233 yr by Karl Daschner

20 minutes ago, Karl Daschner said:

Hi guys

Got a new Sunsynk 5kW installed with zero pv panels yet and a 5.1kW locally produced Navitas lifpo4 wall mounted batt. 2/5 times when AC returns after loadshitting the inverter drops the normal light and power goes down in my home. No fault code logged. Within 60sec it resets itself and reconnects. I have  tried to play with the settings - reduced reconnect time to 10s, upped and downed the trip frequency and voltages etc. Also set charge current to 40A and discharge current to 90A

I also have the NE bonding relay installed and Islanding mode active. It works as intended. I fed the inverter from a 40A DP circuit breaker.

Not sure if this is a inverter fault perhaps or what?

Thanks

Without information like the actual grid voltage when the grid returns one cannot just guess. The best will be to have a small voltmeter connected to the grid so that you can see what the grid voltage is on return. Grid voltage varies between each mini sub based on setting/load and supply from the grid. Some areas are pretty erratic. 

The grid frequency is not something we even need to consider provided your setting is with the 49-51Hz range but can be set wider. 

Edited April 21, 20233 yr by Scorp007

15 minutes ago, Scorp007 said:

Without information like the actual grid voltage when the grid returns one cannot just guess. The best will be to have a small voltmeter connected to the grid so that you can see what the grid voltage is on return. Grid voltage varies between each mini sub based on setting/load and supply from the grid. Some areas are pretty erratic. 

The grid frequency is not something we even need to consider provided your setting is with the 49-51Hz range but can be set wider. 

Thanks, I would of thought that if that is the case, the inverter should log the reason for the trip, but it does not?

8 minutes ago, Karl Daschner said:

Thanks, I would of thought that if that is the case, the inverter should log the reason for the trip, but it does not?

Cannot comment on logging of faults. 

I had this on my Deye ... whenever the power came back it tripped. It was supposedly a bad (read badly installed) changeover switch which made voltage spike to 500V. In the end, the switchover *and* inverter were replaced. This and multiple other stuff ups put the man out of business.  

Is it just the inverter that is tripping ? any earth leakage units that trip aswell? Sounds like a possible wiring issue.

Hi Nexuss

No ELU or breakers trip. Its almost as if the inverter change over just hangs in the middle not changing over to the grid non inverter side. But it is totally random. only does it 25% of the time about. rest works 100%

Edited April 21, 20233 yr by Karl Daschner

Just had volt meter over inverter output. When I switch mains off voltage stays constant at around 228VAC. After returning grid and the waiting period is over where the inverter goes back from the DC circuit to the AC I picked up a spike of over 700V!

Surely this points to an internal inverter fault?

3 hours ago, Scubadude said:

I had this on my Deye ... whenever the power came back it tripped. It was supposedly a bad (read badly installed) changeover switch which made voltage spike to 500V. In the end, the switchover *and* inverter were replaced. This and multiple other stuff ups put the man out of business.  

Thanks, so this was due to an inverter fault then?

18 minutes ago, Karl Daschner said:

Just had volt meter over inverter output. When I switch mains off voltage stays constant at around 228VAC. After returning grid and the waiting period is over where the inverter goes back from the DC circuit to the AC I picked up a spike of over 700V!

Surely this points to an internal inverter fault?

I would try removing the wires from the inverter output /ups and see if you still get the high voltage spike.

thanks will do so

On the Sunsynk app under Equipment/Custom you will have a button labelled "parameter",

Open up that screen and select "F-grid" and "V-grid-L1" and click Confirm.

It should plot a graph of grid frequency and grid voltage:

Do you see any anomalies in that graph? You should not really see a grid frequency that deviates anything, and a grid voltage between 230V and 250V.

What exactly is tripping? Is it breakers on your DB, or is it the inverter itself? 

58 minutes ago, suds7162 said:

On the Sunsynk app under Equipment/Custom you will have a button labelled "parameter",

Open up that screen and select "F-grid" and "V-grid-L1" and click Confirm.

It should plot a graph of grid frequency and grid voltage:

Do you see any anomalies in that graph? You should not really see a grid frequency that deviates anything, and a grid voltage between 230V and 250V.

What exactly is tripping? Is it breakers on your DB, or is it the inverter itself? 

Hi, will do. No breakers trips only the inverter. As the grid power returns the AC light comes on and the Normal light falls away. Then power on all essential circuits drop away and all dials on inverter goes to 0kW. within 60sec or so it resets itself.

Edited April 21, 20233 yr by Karl Daschner

Checked Grid input Frequency and voltage are 100% stable and normal

16 hours ago, Karl Daschner said:

Hi guys

Got a new Sunsynk 5kW installed with zero pv panels yet and a 5.1kW locally produced Navitas lifpo4 wall mounted batt. 2/5 times when AC returns after loadshitting the inverter drops the normal light and power goes down in my home. No fault code logged. Within 60sec it resets itself and reconnects. I have  tried to play with the settings - reduced reconnect time to 10s, upped and downed the trip frequency and voltages etc. Also set charge current to 40A and discharge current to 90A

I also have the NE bonding relay installed and Islanding mode active. It works as intended. I fed the inverter from a 40A DP circuit breaker.

Not sure if this is a inverter fault perhaps or what?

Thanks

1. Do you have comms with the battery, or are you using AGM voltages? I know that it appears to be unrelated, but using an unsupported battery is something that very few Sunsynk users do and it may be related. Plus I am curious to see whether the Navitas battery is supported or not.
2. Are you able to reproduce the fault consistently by tripping the grid mains breaker? If so, reduce the essentials load to next to nothing (maybe 2-300W) and try again?
3. Have you tried a factory reset? The PIN is 9999. 
4. When the grid comes back, it is usually unstable for the first few minutes because the whole neighbourhood is busy load-shifting. It is therefore logical to increase the reconnect time, not decrease it. I have mine set to 600s.
5. Are you running any non-essential loads? If so, turn them off and see if it makes a difference? The thought here is that non-essential loads are usually quite hungry, and if they are busy starting up, may cause grid instability. Also, is your CT coil installed correctly?
6. You haven't given us an indication of what your grid setup is. Have you tried increasing the latitude between highs and lows of grid voltage and frequency? And if this does not work, maybe decreasing the latitude a bit? Make it fussier about what it tries to sync with.

 

If testing the above does not work out, then RMA the unit (after testing with a borrowed battery that has inverter comms).  

Edited April 21, 20233 yr by YellowTapemeasure

Hi. Navitas has good comms via CAN bus to the onboard BMS.

I have played with all of those settings with slight success. Still I would expect to see a over Voltage or frequency fault log which does not come up. 

Ct coil correctly installed and correct way round.

From switching mains on and off have managed to trip my essential side ELU twice and reset the inverter. But that happens also only about 1 in 7 attempts.

Very little load is being pulled by non essnetial or non essential on grid return. I have checked. I only utilize around 15kWh in a 24h period. Inverter barely pulls 2kW on essential side. 

Only thing to still try is to put a permanant link in the inverter bonding load N to E and removing the bonding relay.

Hi guys

 

Just a quick update on my problem. Was lucky to meet an old friend at a school rugby game whom is a solar installer. He suggested I remove the NE contactor and install a solid link in the inverter itself. Since doing this I had 0 further trips!

Cheers