Issue:
Code requirements dictate fusing on Industrial Control Transformers
Product Line:
LV Transformers
Environment:
Applies to Industrial Control Transformers by SquareD/Schneider Electric
Cause:
Industrial Control Transformers by SquareD/Schneider Electric have provisions for 3 fuses
Resolution:
There are fuse mounting provisions for 2 primary fuses (rejection type) and 1 secondary fuse (either rejection or non-rejection type.) Industrial Control Transformers are typically fed by 2 hot, or ungrounded, lines and Code requires that both leads have OCP (Over Current Protection.) The output is typically one hot conductor and one grounded conductor (commonly called a `neutral`.) Code does not permit the grounded conductor to be broken, thus no OCP device can be used on that conductor.
The following video covers installing primary and secondary fuses on 9070 Type TF Industrial Control Transformers: