Hi All,
I am installing a .75Kva transformer (buck boost)to increase our building voltage of 202 up to 222 so that a vaccum pump will operate. When looking at chart 450.3 b, I was a bit confused. I interpreted to mean that as long as my primary was not above 125% of the transformer's rated input current, then no secondary ocpd is required. In this case my primary ocpd is the branch circuit's 2-pole 20 amp breaker.
I was thinking though that it may not be a bad idea to install a double circuit enclosure with another 2-pole 20 amp breaker in it on the secondary side (next to the equipment) and have that double as the equipment disconnect and secondary protection. Does this sound like a good idea? Is my logic accurate? (Oh and for what its worth, the motor has a draw of 16amps at 208-230 volts.
Thank you for your time and input.
I am installing a .75Kva transformer (buck boost)to increase our building voltage of 202 up to 222 so that a vaccum pump will operate. When looking at chart 450.3 b, I was a bit confused. I interpreted to mean that as long as my primary was not above 125% of the transformer's rated input current, then no secondary ocpd is required. In this case my primary ocpd is the branch circuit's 2-pole 20 amp breaker.
I was thinking though that it may not be a bad idea to install a double circuit enclosure with another 2-pole 20 amp breaker in it on the secondary side (next to the equipment) and have that double as the equipment disconnect and secondary protection. Does this sound like a good idea? Is my logic accurate? (Oh and for what its worth, the motor has a draw of 16amps at 208-230 volts.
Thank you for your time and input.
