ABSTRACT
Voltage regulation: The percent voltage drop of a line (e.g., a feeder) with respect to the receivingend voltage. Therefore,
% regulation = −
× V V
100 (9.1)
Voltage drop: The difference between the sending-end and the receiving-end voltages of a line
Nominal voltage: The nominal value assigned to a line or apparatus or a system of a given voltage class
Rated voltage: The voltage at which performance and operating characteristics of apparatus are referred
Service voltage: The voltage measured at the ends of the service-entrance apparatus
Utilization voltage: The voltage measured at the ends of an apparatus
Base voltage: The reference voltage, usually 120 V
Maximum voltage: The largest 5-min average voltage
Minimum voltage: The smallest 5-min voltage
Voltage spread: The difference between the maximum and minimum voltages, without voltage dips due to motor starting
In general, performance of distribution systems and quality of the service provided are measured in terms of freedom from interruptions and maintenance of satisfactory voltage levels at the customer’s premises that are within limits appropriate for this type of service. Due to economic considerations, an electric utility company cannot provide each customer with a constant voltage matching exactly the nameplate voltage on the customer’s utilization apparatus.
