When installing a 1300kva Delta 13.8kv primary, 480vac Delta or Wye secondary. XFMR will have <6% impermanence. Is it necessary to install a fused disconnect on the secondary of the XFMR with OCPD on the primary? Cables will be <25lft.
I've read 240, 450 and 665 (specific to the equipment being installed) but I cannot determine if secondary OCPD is needed. Local contractor indicates it is required but when i review other recent installations i find that they do not include secondary protection?
help in clarification is greatly appreciated.