Chalfont, PA:

Several manufacturers of Arc Resistant ("AR") switchgear and motor control centers (MCCs) have included the ExiscanTM  XIR series IR window in arc resistance tests to prove that the windows do not degrade the protective features of the AR equipment. A major manufacturer of Arc Resistant switchgear recently allowed ExiscanTM engineers to witness one such Arc Resistance Test at KEMA Power Test in Calfont, PA. The test complied with the ANSI/IEEE C37.20.7 Arc Resistance Test procedures. 


Prior to the test, the ExiscanTM XIR-A-4-H infrared window was attached to the enclosure door, roughly in the middle of one of the cable compartments -- a typical position for an IR window. The ignition source was roughly 18 inches from the enclosure door and roughly 15 inches off the bottom of the enclosure. The arc was initiated using a thin gauge wire across phases. Cotton flags were mounted 1” from the seams of the enclosure and around the window. Any escape of heated gases from inside the enclosure would ignite the flags, indicating a failure to contain the arc energy.