What is a wiremap tester?

A wiremap tester is a device that transmits signals through each wire in a copper twisted pair cable to determine if it is connected to the correct pin on the other end.

Wire mapping is the most basic test for twisted pair cables because the eight separate wire connections involved in each length of cable are a common source of installation errors.

These testers detect crossover cables, opens (broken or disconnected wires), and shorts (misconnected wires or pins together), all problems that can cause a cable to fail.

Wiremap testing is almost always included in multi-function cable testers, but in some cases it may not be worth spending thousands of dollars for an all-in-one device. Dedicated testers are relatively inexpensive ($200 to $300) and allow you to test your installation for the most common faults that occur during and after installations.

If you’re installing voice grade cable, for example, a simple wire mapping test may be all you need. There are also slightly more expensive devices (less than $500) that perform wiremap testing in addition to other basic functions, such as TDR length testing.

This type of tester consists of a remote unit that plugs into the other end of a connection and the battery-operated main portable unit that displays the results. Typically, the tester displays various codes to describe the type of faults it encounters. In some cases, you can buy a tester with multiple remote units that are numbered so that one person can test multiple connections without having to constantly travel from one connection to another to move the remote unit.

The only wiring fault that isn’t detectable by a dedicated tester is split pairs, because even though the pins are wrong, the wire is still directly connected. To detect split pairs, you must use a device that tests the cable to detect the near crosstalk caused by split pairs.

Each cable run must receive a minimum level of testing. You can buy $5,000 cable testers that will give you many statistics on performance, but the most important test is simply determining that the pairs are connected correctly.

The $5,000 testers give you much more performance data than simple cable testers and will also certify that each cable run will perform at a specific performance level. Some customers will insist on seeing the results of the $5,000 wire tester, but the minimal tests you must perform will determine continuity and verify that the wire map is correct. You can perform a couple of test levels. Cable testers that you can use include the following:

1. Tone generators and amplifier probes.

2. Continuity Testers

3. Wiremap Testers

4. Cable certification testers