Q:"Which of these Seperately Derived Systems (SDS) may use the OCPD on the Primary side to protect the Secondary side feeders - and why?"
A: (A)
240.(C)(1) & 450.3 (B)
I was thinking "A", "B" and "E" would qualify, as they all have a "Single" Secondary Output Voltage", whereas "C", "D" and "F" would nt qualify, as they have Multiwire Secondaries.
Scott35