Facility Connection RequirementsMay 1, 2005
III. D. Operations and Safety
Interconnections between FPL-NED's transmission system and other transmission systems are normally operated in parallel unless otherwise agreed. However, if any operating condition or circumstance creates an undue burden on the FPL-NED Transmission System, FPL-NED shall have the right to open the interconnection(s) to relieve its system of the burden imposed upon it. Prior notice will be given to the extent practical. Each party shall maintain its system and facilities so as to avoid or minimize the likelihood of disturbances which might impair or interrupt service to the customers of the other party.
The FPL-NED and ISO-NE shall be notified prior to any maintenance work on a transmission interconnection. FPL-NED switching and safety procedures shall be strictly adhered to when maintenance is being performed on an interconnection.
III. E. Metering
Metering equipment may be located at either end of the transmission line but should be installed at the station closest to the change of ownership. Metering shall be designed and installed in accordance with ISO-NE policies, rules, procedures and standards, including but not limited to ISO-NE OP-18 (Metering and Telemetering Criteria).
III. F. Protection
The relay protection criteria under Section I is to be adhered to for utility-to-utility interconnections. When distribution load stations are looped on a transmission line, special consideration must be applied. Directional comparison blocking schemes are preferred. If permissive overreaching transfer trip (POTT) is used with fiber, the communications echo feature must be employed. This is required to ensure high-speed fault clearing when the line is open at a distribution station between the transmission terminals.
When ground distance relaying is used on short lines, the quadrilateral characteristic is to be used to provide adequate coverage for fault resistance.
Directional ground overcurrent protection should only be used after cafefull study on lines that have considerable mutual coupling with other circuits. Sensitive instantaneous directional ground overcurrent relays can cause false operation on circuits with looped distribution load stations due to switch pole asynchronism and should be avoided in such cases.
III. G. Transmission Reclosing
Automatic reclosing on interconnected transmission lines between utilities is handled based on ISO-NE policies and standards. High speed automatic reclosing must be avoided at generation substations.