Clean wire preparation is the foundation of every reliable electrical connection. Nicked strands, uneven insulation and the wrong strip length all lead to weak joints. These steps apply to low-voltage and hobby projects. Work on mains wiring only if you are qualified and the circuit is isolated.
Step by step
- Confirm the circuit is powered down and cannot be switched on by someone else
- Select the stripper hole that matches the conductor size
- Close the jaws just enough to cut the insulation, not the copper
- Pull the insulation off in one smooth motion
- Inspect the strands: none should be cut, and the end should be bright and clean
Strip length matters
The connector manufacturer states how much bare wire should enter the terminal. Too short and the crimp grips insulation, too long and bare copper is left exposed. Measure the first one against the connector, then match the rest to it.
Finish with a pull test
Once the terminal is crimped or tightened, tug each wire firmly. A joint that holds under a pull will usually hold in service. Label the wire if more than one looks alike, because you will be glad of it later.