jonescg
New Member
Hi All,
I've helped a friend out with her home solar and storage system, and after fixing the ELV (48V) lithium iron phosphate battery with a new BMS (Seplos 3.0) I fired it all up and while it communicates with the inverter okay, the moment it decides it's ready to interact with the grid, it trips it's own isolator (32 A MCB) and the house main breaker (3-gang 32 A MCB). Some details:
Grid connection is a 3-phase + Neutral from Western Power (Australia).
Home has a Sunnyboy grid-tie solar inverter from about 2016 which feeds one phase.
About 4 kW of solar on the roof as two strings for the two MPPTs on the Sunnyboy.
In 2019 she installed a yellow GW5000SBP AC-coupled battery inverter which supports a 48 V LFP battery of about 15 kWh.
This pushes power back down one phase according to the 3-phase EZ-Meter which measures current into and out of the house to manage charge.
The original ZEVA BMS worked for a while, but at some point it didn't, and it simply needed to be reset, but she never did "because it's all too technical!" meaning the battery never got charged for a year. It got well down before anything was done about it. So now there's a rejuvenated battery and a new BMS (Seplos 3.0) which seems to be connecting to the inverter. However, when the inverter is introduced to the grid (the MCB labelled Goodwe AC inverter) is switched on, it goes through a series of checks, and when it decides to connect, the MCB and the house main breaker trip.
I've narrowed it down to the GW5000SBP and it's interaction with the grid, because as long as that MCB is off, it all looks quite normal. Even the Backup circuit appears to have line voltage on it, although it isn't supplying anything in the house as far as I can tell. This inverter was last functioning properly years ago and probably never got turned off since the BMS wigged out and ran the pack down.
She did mention that after a very heavy downpour of unusual March rain (we call autumn 'pole-top fire season') that the grid-tie solar inverter was tripping out, however that seems to have fixed itself after the place dried out. There's a chance the GW5000SBP has a similar problem.
The place is due to be visited by a friendly Electrical Contractor so he can look at the LV stuff (my competent hands stop at 120 V dc) so hopefully he might have a chance to pull the distribution panel apart and look for any clues.
So I ask the brains trust - is this something you've encountered before? Would we be better off putting the inverter on marketplace and swapping the Sunnyboy for a GW5048ES hybrid inverter instead? They're like, $1600 now, so pretty affordable.
Cheers,
Chris
I've helped a friend out with her home solar and storage system, and after fixing the ELV (48V) lithium iron phosphate battery with a new BMS (Seplos 3.0) I fired it all up and while it communicates with the inverter okay, the moment it decides it's ready to interact with the grid, it trips it's own isolator (32 A MCB) and the house main breaker (3-gang 32 A MCB). Some details:
Grid connection is a 3-phase + Neutral from Western Power (Australia).
Home has a Sunnyboy grid-tie solar inverter from about 2016 which feeds one phase.
About 4 kW of solar on the roof as two strings for the two MPPTs on the Sunnyboy.
In 2019 she installed a yellow GW5000SBP AC-coupled battery inverter which supports a 48 V LFP battery of about 15 kWh.
This pushes power back down one phase according to the 3-phase EZ-Meter which measures current into and out of the house to manage charge.
The original ZEVA BMS worked for a while, but at some point it didn't, and it simply needed to be reset, but she never did "because it's all too technical!" meaning the battery never got charged for a year. It got well down before anything was done about it. So now there's a rejuvenated battery and a new BMS (Seplos 3.0) which seems to be connecting to the inverter. However, when the inverter is introduced to the grid (the MCB labelled Goodwe AC inverter) is switched on, it goes through a series of checks, and when it decides to connect, the MCB and the house main breaker trip.
I've narrowed it down to the GW5000SBP and it's interaction with the grid, because as long as that MCB is off, it all looks quite normal. Even the Backup circuit appears to have line voltage on it, although it isn't supplying anything in the house as far as I can tell. This inverter was last functioning properly years ago and probably never got turned off since the BMS wigged out and ran the pack down.
She did mention that after a very heavy downpour of unusual March rain (we call autumn 'pole-top fire season') that the grid-tie solar inverter was tripping out, however that seems to have fixed itself after the place dried out. There's a chance the GW5000SBP has a similar problem.
The place is due to be visited by a friendly Electrical Contractor so he can look at the LV stuff (my competent hands stop at 120 V dc) so hopefully he might have a chance to pull the distribution panel apart and look for any clues.
So I ask the brains trust - is this something you've encountered before? Would we be better off putting the inverter on marketplace and swapping the Sunnyboy for a GW5048ES hybrid inverter instead? They're like, $1600 now, so pretty affordable.
Cheers,
Chris
