212, if the S-92 is similar to the Hawk series (S-70 derivatives) IIRC the main generators dropoff when Nr droops in the Nr = low 90's high 80's. (The number in my memory is 92% but that might not be right).
EDIT: Heh,
memory is not all bad ... from the FCF checklist a few iterations ago ...
b. Underfrequency protection — Test.(1) No. 1 and No. 2 PCLs — Retard slowly.
(2) #1 GEN and #2 GEN cautions — Appear between 92 and 97 percent N
r. Allow a 3-second time delay. Note Nr.
(3) No. 1 and No. 2 PCLs — FLY. Note #1 GEN and #2 GEN cautions disappear.
I think that in the Cougar mishap, the backup generator (powered by the APU) was up and running. That said, in the Hawk series, the switch over from #1 / #2 gen to Backup Gen powering the various AC and DC busses isn't what I'd call seamless. (TYpically SAS and AFCS kick off, though I don't think Boost would kick). I'll guess it isn't in the S-92. (I think this has been addressed both in this thread, and in the TSBoC report).
EDIT: More data that my memory isn't completely shot.
Power transfer from the APU generator or EXT PWR to the No. 1 generator may cause disengagement of SAS 1, SAS 2, TRIM, AUTO PLT, and stabilator.
SansAn ... thanks for the training manual, it restores a bit that was lost in memory.