Low Voltage Cable Insulation Tester
The Insuleak™ system redefines cable’s insulation test standards. It was designed by Hydro-Quebec to prevent majors failures in power distribution cables. The Insuleak™ uses a unique process of air injection in the cable’s core, and pressure monitoring for a determined period of time. The Insuleak™ is a great innovation for detection insulations flaws in low voltage insulated cables.
The test method consist of injecting air pressure in the core of the low voltage cable. The air pressure is then monitored to detect any fluctuation. The presence of insulation failure is detected when the air pressure cannot be contained in the cable for the determined period of time.
Numerous tests were done at Hydro-Quebec’s laboratory to develop a test method. This method is able to meet the performance requirements specified for implementation on Hydro-Quebec’s distribution network. Several variants were assessed on the optimal way of injecting air into the cable and the effectiveness of detecting a small leak. The tests were conducted with different types of calibrated faults that were simulated by perforating the layer of electrical insulation up to the cable core following this process, three variants of the new method for verifying LV cable insulation were selected.
Low voltage cable installation can damage the cable’s insulating material. Since the cables are pulled in the underground ducks, it is not possible to visually inspect their condition after the installation. If the cable’s insulating material was damaged while performing this process, it may degrade rapidly, create electrical arcs and even explode in certain conditions.