Hello,
I am currently installing a 208v delta to 480v wye transformer to supply a milling machine. I have done my homework but I am second guessing myself on this so I could use another opinion.
I have calculated my primary breaker to be 156 amps which I will raise up to 175a.
I will be using 2/0 as feeders
My secondary will be rated @ 70 amps and protected by a fused disconnect.
I will be using #6
My grounding will be a #6
Are my conductors overkilled?
This particular machine only needs 440 volts and needs a 40 amp circuit, the machine is also internally fused at 40 amps.
I will go from my equipment ground on the machine, to my disconnect then to the case on the transformer. I will bond the XO of my secondary side to the case of the transformer then building steel (right next to the transformer).
one of my concerns is when I pipe my primary to the transformer will this become another path to ground?
I have seriously confused myself.....maybe im just getting old
any help would be appreciated
I am currently installing a 208v delta to 480v wye transformer to supply a milling machine. I have done my homework but I am second guessing myself on this so I could use another opinion.
I have calculated my primary breaker to be 156 amps which I will raise up to 175a.
I will be using 2/0 as feeders
My secondary will be rated @ 70 amps and protected by a fused disconnect.
I will be using #6
My grounding will be a #6
Are my conductors overkilled?
This particular machine only needs 440 volts and needs a 40 amp circuit, the machine is also internally fused at 40 amps.
I will go from my equipment ground on the machine, to my disconnect then to the case on the transformer. I will bond the XO of my secondary side to the case of the transformer then building steel (right next to the transformer).
one of my concerns is when I pipe my primary to the transformer will this become another path to ground?
I have seriously confused myself.....maybe im just getting old
any help would be appreciated