Electrical Cable Insulation Testing Procedure

We verify the electrical insulation level in any device such as a motor cable and transformer.

Electrical cable insulation testing procedure. Whether the dielectric is good or bad to evaluate a number of test results on the same piece of equipment you have to conduct the test the same way and under the relatively same environmental parameters each and every time. Locate the connection point of the wire or cable you want to test so you have access to the exposed conductors. The main reasons to test a new electrical installation or house. Temperature humidity moisture and dust particles.

The insulation test combines several functions. The result of this can be measured in terms of mega ohm. Insulation resistance test data may be used to establish a trending pattern. The procedure for vlf testing is nearly identical to that of dc hi pot testing and is also conducted as a go no go test.

A cable insulation test is basically a continuity test so the power to the circuit must be off. Deviations from the baseline information permit evaluation of the insulation. To measure electrical leakage in wire we pass the current through devices then. The insulation test proceeds as follows.

Vlf testing of cables is supported in iec 60502 up to 35 kv and in ieee 400 2 up to 69 kv. Table 100 22 minimum radii for power cable. The dielectric withstand test is a basic electrical stress test conducted to ensure an insulation system will provide adequate service life. The megger test is a method of testing making use of an insulation tester resistance meter that will help to verify the condition of electrical insulation.

From 20v to 2000v. When your plant electrical system and equipment are new the electrical insulation should be in top notch shape. Measurement of dielectric strength and detection of short circuits. Nevertheless even today insulation is subject to many.

As higher voltage vlf equipment is developed standards may be adapted to increase the voltage level for application. If the cable can withstand the applied voltage for the duration of the test it. Electrical installation testing procedures 3 comments basic concepts by ajay sharma all new completed electrical installation should be tested before connection to the supply to ensure that the installation is technically sound and free from any possible short circuits etc. Test results are dependent on the temperature of the insulating material and the humidity of the surrounding environment at the time of the test.

Dc testing has also been shown to reduce the remaining life of cables with aged polymer insulation. Determining insulation resistances from fifty kilo ohm to two thousand mega ohm at high voltage i e. Insulation resistance quality of an electrical system degrades with time environment condition i e. The vlf test can be used in a.

Because electrical insulation will exhibit dynamic behavior during the course of your test. Furthermore manufacturers of wire cable motors and so on have continually improved their insulations for services in industry.