Although G&T devices have been used as accessory devices in metal-clad switchgear for decades, they were not addressed in the standards until IEEE Std C37.20.6™-1997 was approved. This is because they are specialized accessory devices, designed and tested in accordance with applicable sections of circuit breaker standards and based on user-unique operational requirements. This revised standard complements IEEE Std C37.20.2 and IEEE Std C37.20.3 and addresses the more common G&T device types. This standard also clarifies that G&T devices are not required to have either the interrupting or continuous current ratings of the circuit breakers they may temporarily replace for the purpose of grounding and testing medium-voltage circuits. It also recognizes that some devices may be offered with interrupting capabilities, and required tests for such devices are specified.
Revision Standard – Active. Drawout-type ground and test devices for use in medium-voltage metal-clad switchgear rated 4.76 kV through 48.3 kV are covered by this standard. The description, design, and testing of these accessory devices that are inserted in place of drawout circuit breakers for the purpose of grounding and testing are also covered.