Omega d2 help

I recently picked up this enlarger in trade and am not sure how to hook
up electric properly. This is a omega d2 with a super chromega dichroic
lamphouse. It also has a solid state voltage stabilizer on the back
of the power supply. I was also given a larger transformer that seems
to knock 120vac down to 100vac it has 1 male and 1 female plug coming
from it. The lamphouse power supply has a voltage rating on the back of
100v - 117v the transformer doesn't have any rating plate or
manufacturer name. I have the enlarger manual and it says nothing about
the need of a transformer.

My question: Do I need this transformer or should I simply plug the
power supply into a standard outlet.


any help would be appreciated,

John T