During the current flow electrical resistance occurs at the point of contact between conductor and connector. The more secure the connection is, both mechanically and electrically, the less resistance there will be.

Increased resistance is disadvantageous for

 

• signal transmission because the signal flow is attenuated (weakened);
• power transmission because energy is lost and contacts are heated (risk of fire).

It is measured by means of an ohmmeter connected to the plug and the conductor.