Technical information

FEEDER AND BRANCH CIRCUITS

added to both values.The two values obtained are considered FLA and LRA of a

single virtual motor representing the full machine, the power of which (in HP)

can be obtained from the tables for example tab 50.1 of UL 508A).

The switching device should have an hp size above that of the virtual motor

(remember that the LRA of the switch is set at 6 times the FLA exactly like the

conductors).

In the case of components c

haracterized both in pow er and in curr ent both

sizing are applied: if however the component is specially approved for motor

switching (e.g. manual motor controller) the sizing in current is not necessary.

2.4 Conforming components that can be used for disconnecting

means

The devices that can be used for switching and protection of the electrical

equipment of the machines are:

•Circuit breaker conforming with UL 489

•Switches with or without fuse UL 98.

140U

2.5 Components that cannot be used for disconnecting means

•Circuit breaker conforming with UL 508 certified as Manual Motor Controllers

•Switches with or without fuses conforming with UL 508A certified as Manual

Motor Controllers

The limitation of these components is connected with the location of the

command and control in the electrical equipment. In particular the use

and installation of these components is not permitted in feeder circuits

in North America.