Question

Crimping Lugs Practical 

Answer 1

Practical Significance

Lugs or connectors are used at the cable ends, when permanent, direct fastening methods are not feasible or necessary. Cables are connected to bus bars with the help of lugs and nut—bolts.

Competency and Practical Skills

This practical is expected to develop the following skills for the industry identified competency: ‘Plan wiring/cabling activities using relevant materials following safe practices’

i. Select proper tools for cable leads crimping.

ii. Use crimping tool crimping process

iii. Prepare leads crimping.

Practical Outcome

1. Perform lug crimping for cable leads of a specific size.

2. Perform lug crimping for cable leads of a size other than above.

Relevant Affective domain related Outcome(s)

i. Practice good housekeeping with safety measures.

ii. Demonstrate working as a leader/a team member.

iii. Maintain tools and equipment.

iv. Follow ethical practices.

Minimum Theoretical Background

The word crimping in this context means to join two pieces of metal together by deforming one or both of them to hold the other. The deformity is called the crimp. The cable conductors are joined to bus bar or distribution box using a special connector known as cable lug. Stripped wire (often stranded.) is inserted through the correctly sized opening of the connector, and a crirnper is used to tightly squeeze the opening against the wire. Depending on the type of connector used, it may be attached to a metal plate by a separate screw or bolt or it could be simply screwed on using the connector.

An electrical connector is a device for joining electrical circuits together using a mechanical assembly. The connection may be temporary or serve as a permanent electrical joint between two wires.

There are hundreds of types of electrical connectors. Connectors may join two lengths of wire together or connect a wire to an electrical terminal.

Practical set-up / Circuit diagram / Work Situation

Resources Required

Precautions to be followed

1 Take care to prevent cutting of wire conductors, uneven stripping length and insufficient cutting of the insulation.

2 Ensure the strands do not spray come apart.

3 Do not excessively twist the strands.

4 Use proper size of the lug according to size of cable.

Procedure

1. Select the cable of appropriate size (for example 16 sq.mm)

2. Select the lug of the proper size.

3. Measure the dimensions of cable and lug.

4. Remove the insulation of the cable as per the measured dimension.

5. Both cable conductor and compression crimp should be cleaned down using cable cleaning wipes.

6. Check size, shape and metal (copper or aluminum) must be correct for the cable conductor.

7. Select correct crimp die set.

8. Check cable conductor is be fully inserted into the crimp connector

Note: The correct compression or crimping sequence must be followed and the full compression pressure applied.