I came across another instance which I believe is a violation of the tap rule and wanted to hear others thoughts.
A 480V panel is being fed from an upstream 400A fused switch with a 600MCM cable. The 480V panel is a MLO and does not have a main breaker. Tapped directly off of the bus in this panel a #4AWG cable which goes on to feed another 480V MLO panel about 50ft away.
Looking at this I find this to be a violation of 240.21(B)(4) for a number of reasons:
1) Tap conductors are over 25ft long horizontally.
2) The 85A capacity of the #4 tap conductors is less than 1/3 (133A) the upstream 400A fused switch
3) The tap conductors terminate into a MLO panel and therefore do not terminate into a single OCPD.
Do you guys agree?
A 480V panel is being fed from an upstream 400A fused switch with a 600MCM cable. The 480V panel is a MLO and does not have a main breaker. Tapped directly off of the bus in this panel a #4AWG cable which goes on to feed another 480V MLO panel about 50ft away.
Looking at this I find this to be a violation of 240.21(B)(4) for a number of reasons:
1) Tap conductors are over 25ft long horizontally.
2) The 85A capacity of the #4 tap conductors is less than 1/3 (133A) the upstream 400A fused switch
3) The tap conductors terminate into a MLO panel and therefore do not terminate into a single OCPD.
Do you guys agree?