Glossary

Crimp connection

Also Compression connection

What is Crimp connection?

A connection in which a cable lug is pressed onto the stranded wire with a defined force. On board it is the standard connection — mechanically strong, gas-tight and permanently conductive.

What matters about Crimp connection in practice?

The right tool is decisive. A connection squeezed with combination pliers looks similar but holds neither mechanically nor electrically — and only shows up under load or after years.

Tinned wire ends do not belong in screw terminals: the tin flows under pressure and the terminal loosens. The right choice is crimped cable lugs or wire ferrules, plus strain relief at every connection.

How do you recognise a good crimp connection?

  • Cable lug and strand match in cross-section. On insulated lugs, the colour shows the range: red 0.5 to 1.5 mm², blue 1.5 to 2.5 mm², yellow 4 to 6 mm².
  • The strand reaches the end of the barrel, no wire sticks out.
  • The crimp impression sits on the barrel, not on the insulation.
  • Pull hard on the cable and nothing moves.

Which tool do I need?

For insulated lugs, a ratchet crimper with matching dies. The ratchet only releases once full crimping force is reached, which makes every connection equally good. Large tubular lugs on battery and main cables need a hexagonal or hydraulic crimper matched to the cross-section.

Crimp or solder?

On board, you crimp. Solder stiffens the strand at the transition, and that is exactly where it breaks under vibration. If you want to seal the connection as well, use adhesive-lined heat shrink over it. The cable configurator supplies ready-made cables in the length you need.

Related terms

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Still unclear?

We are happy to explain it for your specific case.

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