Fred Shenkman
Member
- Location
- Ny,Ny
Hello all,
This is for elevator application where iso transformer directly supplies a KEB pwm a/c drive.
Looking for input and advise on sizing primary side and properly fusing same. Following is example to use. 85kva 460/460 3 phase.
So using kva=V*I*1.732/1000 would give me 106.69A.
Typically would use THHN #2 or #1 depending on run length?
What would be the rule of thumb for picking proper fuse size?
Side note,I realize that this is not really a influence to the questions but the elec insp used this in his violations, Gearless PM motor being used with following data: 174V, 105A, 32HP.
He commented that that if time delay fuse in mainline it should be 106x175% or for non time delay 106x300%. Thats crazy!
This is for elevator application where iso transformer directly supplies a KEB pwm a/c drive.
Looking for input and advise on sizing primary side and properly fusing same. Following is example to use. 85kva 460/460 3 phase.
So using kva=V*I*1.732/1000 would give me 106.69A.
Typically would use THHN #2 or #1 depending on run length?
What would be the rule of thumb for picking proper fuse size?
Side note,I realize that this is not really a influence to the questions but the elec insp used this in his violations, Gearless PM motor being used with following data: 174V, 105A, 32HP.
He commented that that if time delay fuse in mainline it should be 106x175% or for non time delay 106x300%. Thats crazy!