Hello,

I am using this table correct.

I have a 1kVA transformer and need to calculate OPCD size.

Data:

480V 3 phase to 120V 1 phase transformer

8 amp load for secondary side.

1. I calculate 3.5amp OPCD size. 1.67 x (1000/480) = 3.479amp. Is this correct?

2. How do i determine to use OPCD on primary and secondary?

3. Do I need a fuse on the secondary side to protect the conductors?

Thank you.

I am using this table correct.

I have a 1kVA transformer and need to calculate OPCD size.

Data:

480V 3 phase to 120V 1 phase transformer

8 amp load for secondary side.

1. I calculate 3.5amp OPCD size. 1.67 x (1000/480) = 3.479amp. Is this correct?

2. How do i determine to use OPCD on primary and secondary?

3. Do I need a fuse on the secondary side to protect the conductors?

Thank you.

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