Technical information

FEEDER AND BRANCH CIRCUITS

The designer is limited in the choice and use of some components because the

standard provides that the starts of the motor be realized exclusively with UL 248

fuses or UL 489 circuit breaker contactor and thermal relay.

On the other hand, if disconnecting devices are planned with the feeder

protection function, there are no restrictions in the use of the components in the

electrical equipment.

Feeder: all the conductors and the circuits up line from the last overcurrent

protection device of a branch (branch circuit).

BCPD: Overload protective device (e.g. circuit breaker fuses).

Branch Circuit: the conductors and the components down line from the last

over current protection device and the load Branch Circuit #1 Branch Circuit #2

4. Internal wire

The internal distribution of a industrial control panel is normally made with a line

of conductors that power the distribution terminal strip from which the

conductors with a smaller cross-section are derived and that power the protection

devices of the individual branch circuits.Alternatively, a bar system by which the

conductors are derived directly at the BCPs. in the case of high currents can be

used

It is necessary to distinguish between:

• “Feeder conductors”: the conductors/bars or larger cross sections:

• “Tap conductors”: any derivations of smaller cross sections that power the

branch circuits.