scope:

This guide contains information on a number of different protective relaying practices for the utility-consumer interconnection. It is intended to cover applications involving service to a consumer that normally requires a transformation between the utility's supply voltage and the consumer's utilization voltage. Interconnections supplied at the utilization voltage are not covered.

This guide is not intended to supplant specific utility or consumer practices, procedures, requirements, or any contractual agreement between the utility and the consumer. The examples in Clause 7 are used for illustrative purposes only and do not necessarily represent the preferred protection under all conditions.

This guide addresses consumers, with or without generation, that are connected to utility subtransmission or transmission circuits. The specific control schemes associated with generation are not addressed. It is not intended to apply necessarily to consumer generation connected to utility distribution circuits.