SAFEGUARDS FOR INSTALLING WIRES AND CABLES

Steps in safeguarding wires and cables when installing it in conduits.

Investigations have shown that cable failures often can be attributed to damage caused during installation due to carelessness, inexperience and inability to observe certain simple precautions. In order to eliminate such preventable causes of electrical shutdowns and loss of production, the following procedures should be followed:

BEFORE PULLING WIRE/CABLE

(1) Know and observe all Philippine Electrical Code rules regarding installation.
(2) Check the conduit and wire/cable sizes and actual overall diameters in order to be sure that the approved "fill" will not be exceeded. Do not "crowd" the conduit.
(3) Check the type of wire/cable to be installed.
(4) Consider the use of larger conduits or additional pull boxes.
(5) Check any obstruction on the conduit.
(6) To loosen any burrs, pull a short mandrel or plug closely approximating the diameter of the conduit and clean out any remaining dirt or foreign matter, follow it up with a swab.

WHILE PULLING WIRE/CABLE

(1) To prevent short bends, sharp edges and "crossover", always have a man feed wire straight into a conduit by hand or over a large diameter sheave for large conductors/cables.
(2) Remove all lashings used for temporary bunching of individual wires/cables before they enter the conduit.
(3) Lead-out wires at all pull boxes and conduits. Feed them in again for the next run.
(4) Never pull directly around short right angled bends.

AFTER PULLINGWIRE/CABLE

Shut off the exposed ends of the excess wire/cable on the reel with a tape to prevent moisture from entering the wire/cable.

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