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dallas-cass avatar image
dallas-cass asked

Three Phase Phase rotation Issue

Hi, we have a site that comprises of 3 x Multiplus 5KVA II's which is DC coupled with MPPT's. It has been running seamlessly for a couple of years, however this last week one of the inverters has been going into overload and then the system has phase rotation warnings.

The phase in question has stable grid frequency and voltage, and the load is the lowest of the three phases.

We are planning to replace the inverter, however does anyone have any ideas with regards to possible firmware issues or any other suggestions besides just replacing the inverter?

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3 phase
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bulraydin avatar image bulraydin commented ·
Hi , we have similarly same problem on two sites with same inverter as yours, frequent phase rotation alarms but physically everything is ok. Did you find the root cause ?
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Alexandra avatar image
Alexandra answered ·

@Dallas Cass

Besides all the usual comms cable checking or replacing. Sometimes corrosion on the connections. Have you followed the ve bus error 3 troubleshooting?

https://www.victronenergy.com/live/ve.bus:ve.bus_error_codes#error_3_-_not_all_or_more_than_the_expected_devices_were_found_in_the_system

Unless it is possible ac wiring has worked loose.

Have seen phase rotation once when the incoming grid at the transformer was rotated during repairs.

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Alexandra avatar image Alexandra ♦ commented ·

@Dallas Cass

A suggestion from a colleague was after checking comms and the basics was to change it into a different position physically. It will mean reprogramming the units but will rule out if it is the unit or not. It does affect downtime so need to weigh up the options verses benefits.


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