Ground Fault on my Bergey?

[Pigsywigsy]

Evening all, my Bergey was down to get the blades modified, it went back up on Friday afternoon, noticed on Saturday morning that my generation meter was flashing when the turbine wasn't turning, when I took a look at the Powersync II and the online monitoring page both had a value of a steady -2000w, first time I've seen a -ve value on there. Installers were out today and have eliminated a few things but we've not yet found the cause, suggestions welcome please?

Ta,
Drew

[camillitech]

Water in head whilst it was down? Perhaps needs a good blow to dry out?

Good luck Paul

[Pigsywigsy]

Thanks Paul, it was only down briefly when the blades came off and then back on, unusually for here both days were dry and sunny, it was raised back up for the time inbetween blade-less.

[biff]

I wish I could help,
                     This is a new one on me, I wonder is there a stray wire trapped under a brush on the slip rings,?
                        Bergey and Y/S are first cousins (so I am told) and above 3kw there are six cables to the head rather than the ordinary 3phase, the three extra deal with the motorised furling.
      If there is a load of -2,000watt you need to get it disconnected as soon as possible. There might just be a glitch in the controller but you cannot take a chance.
                                                         Biff
       Or as Paul says, There could be water in the windings that got in while it was lowered.

[Pigsywigsy]

Update on this issue, turbine is now back on but the issue remains the same, when the wind gets up its producing but when the wind dies down it's back into -ve values. Bergey have been consulted but we've no resolution yet.
Any chance when there's  -ve readings that it's actually drawing power from the grid (would need to isolate every other electrical device in the house to prove this 🙄).

[Pigsywigsy]

Very windy here today, Bergey going flat out, would usually be peaking at 12kw in these winds but it's maxing out at just over 7kw, another symptom of the fault but still awaiting a fix 🤔

[biff]

Hi PW,
        It sounds like you have a phase disconnected. i would lower it as soon as possible and get it fixed before it gets damaged permanently.
  It might only be a cable damaged but you have to remember that it depends on the 3 phases to control it in high winds as well as the furling.
 I would not touch the brake if it is a shorting out one..If it is a manual one then fine but if you short it out it will not stop but instead start to heat up the windings.
 I don,t know about you,,but we have another humdinger of a blow on the way. Be careful.
                                                 Biff

[Pigsywigsy]

Thanks Biff, that's a good suggestion, would explain the lower output, I don't apply the brake, it gets left in freerun if it's not on. Awaiting a revisit for further investigations.