The extenders are sealed to porcelain or glass insulators, driving the high leakage currents found in polluted areas around the edge of the extender’s skirt. Each extender adds 6” (150 mm) of creepage to the insulator’s existing creepage distance, reducing the electric stress. They also improve insulator or bushing performance by changing the overall shape to a staggered shed profile. When an extender is required for a previously unused profile, it is straight forward to create. There is no upper voltage limit to the use of creepage extenders. TE has now added a range of cold applied wraparound creepage extenders to its list of TE’s Raychem heat shrink creepage extenders (HVCE-WA’s). This will considerably reduce installation time in situations where heavy metal work or complicated connection geometry makes disconnection on the insulator or bushing difficult.
Cold-applied wraparound creepage extenders work the same way as conventional extenders but leave a gap where the extender has stretched open, allowing it to wrap around the porcelain or glass skirt onto which it is installed.