A
It is obvious that you need qualified assistance. But because your
query smacks of the animal, vegetable, or mineral variety, I'll bite:
1) Are you sure that the noise is emanating from the transformer? Not
elsewhere in the sub?
2) Although your terms "on" and "off" indicate a "cycling" phenomena, is
it continuous (all day)? Or intermittent (certain times)?
3) Although unusual for this size transformer, is it provided with a
TCUL, i.e., tap-changer-under-load?
Regards,
Phil Corso, PE {Boca Raton, FL, USA}
[[email protected]] ([email protected])
