Cable tester

[1] Generally a basic cable tester is a battery operated portable instrument with a source of electric current, one or more voltage indicators, and possibly a switching or scanning arrangement to check each of several conductors sequentially.

The first phase, called the "opens test" makes sure each of the intended connections is good.

There are two common ways to test a connection: There are two common ways to test for a short: More powerful cable testers can measure the properties of the cable relevant to signal transmission.

These include the DC resistance of the cable, the loss of signal strength (attenuation) of a signal at one or more frequencies, and a measure of the isolation between multiple pairs of a multi-pair cable or crosstalk.

While these instruments are several times the cost and complexity of basic continuity testers, these measurements may be required to certify that a cable installation meets the technical standards required for its use, for example, in local area network cabling.