AutoISO-5000 Adapter for Multi-Core Cables
A regular testing program is necessary to examine the present condition of insulation and detect deterioration. Insulation resistance will inevitably trend downwards over time. Periodic testing will indicate whether the deterioration is gradual or more rapid and therefore helps to predict whether to take preventive action immediately or at some future date. The safety of personnel is of paramount consideration and is the main justification for performing insulation testing. Insulation testing is also an important maintenance activity to ensure reliable and continued operation of industrial equipment where downtime can be very costly. Insulation test results for cables and equipment should be recorded, and the most recent results should be compared to their history. Also, keep in mind that the first tests should be done even before equipment is placed into services, such as for new motors, or new cables. The initial reading establishes a baseline to compare to and may indicate faulty equipment or sub-par conductors that ought not to be installed at all.
Testing many cables in a day, whether already installed in a facility, or in a storage area prior to installation, can be a time-consuming exercise. Multi-conductor cables require a specific method of measurement to go through all the combinations to measure the resistance of each conductor relative to each other. For a cable with 4 conductors (A, B, C, G) the operator must manually change test clip connections six times when equipped with only a pair of test leads and clips. (To test the combinations A to B, A to C, C to A, A to G, B to G, C to G). For cables with 5 conductors takes ten connect/ re-connect operations.