Use of Wiring Ferrules in ICPs
Wiring ferrules are commonly used to facilitate connection of internal wiring in industrial control panels. Ferrules are limited to factory installation since specialized tools and control of their use must be applied to the installation. Any manufacturer's insulated or non-Insulated wiring ferrules are suitable for use in panels provided the following conditions are met:
a. Used for factory wiring only, power or control circuits,
b. Crimped with a tool recommended by the ferrule manufacturer before terminating in terminal blocks, wire connectors, or terminals of components such as contactors, disconnect switches, fuseholders, circuit breakers and the like,
c. Sized appropriately for the number of wires and wire size as recommended by the ferrule manufacturer,
d. Identified for use with fine stranded conductors when used with conductors more finely stranded than Class B and Class C stranding, and
e. Crimped to the wires such that the length of the uninsulated portion of the wires does not result in the reduction of electrical spacings below the distances required when the ferrule is installed.
As ferrules are an extension of a conductor, no short circuit current rating is required or assigned. Ferrules are primarily for use with stranded conductors. However, they may be used with solid conductors if identified for such use.
