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Interconnection Guidelines


Wisconsin Interconnection Guidelines Document 31 pages

Glossary Appendix I, Page 20


ANSI – American National Standards Institute.


Applicant — The legally responsible person applying to an electric provider to interconnect a DG facility to the electric provider’s distribution system.


Application Review — A review by the electric provider of the completed standard interconnection application form for interconnection, to determine if an engineering review or distribution system study is needed.


Back-up Power — Electric energy or capacity supplied by an electric provider to replace energy ordinarily generated by DG facility equipment during an unscheduled outage of the distribution system.


Category 1 – A distributed generation facility of 20 kW or less.

Category 2 – A distributed generation facility of greater than 20 kW and not more than 200 kW.

Category 3 – A distributed generation facility of greater than 200 kW and not more than 1 MW.

Category 4 – A distributed generation facility of greater than 1 MW and not more than 15 MW.


Certified Equipment — A generating, control or protective system that has been certified by a nationally recognized testing laboratory (NRTL) as meeting acceptable safety and reliability standards.

Commission — The Public Service Commission of Wisconsin (PSCW).


Commissioning Test — The initial process of documenting and verifying the performance of a DG facility so that it operates in conformity with the design specifications.


Customer — Any person who is receiving electric service from an electric provider’s distribution system.


Designated Point of Contact — Each electric provider shall designate one point of contact for all customer inquiries related to DG facilities and from which interested parties can obtain a copy of interconnection guidelines - which include the appropriate application forms and interconnection agreements.


Distributed Generation (DG) Facility — A facility for the generation of electricity with a capacity of no more than 15 megawatts that is located near the point where the electricity will be used or is in a location that will support the functioning of the electric power distribution grid.

Distribution Feeder — An electric line from an electric provider substation or other supply point to customers that is operated at 50 kV or less, or as determined by the commission.


Distribution System — All electrical wires, equipment, and other facilities owned or provided by an electric provider that are normally operated at 50 kV or less.

Distribution System Study — A study to determine if a distribution system upgrade is needed to accommodate the proposed DG facility and to determine the cost of any such upgrade.


Electric Provider — A public utility or retail electric cooperative that sells electricity at retail in Wisconsin.


Engineering Review — A study that may be undertaken by an electric provider, in response to its receipt of a completed standard application form for interconnection, to determine the suitability of the installation.

Fault — An equipment failure, conductor failure, short circuit, or other condition resulting from abnormally high amounts of current from the power source.


IEEE — Institute of Electrical and Electronics Engineers.


Independent System Operator (ISO) — An entity supervising the collective transmission facilities of a power region; the ISO is charged with nondiscriminatory coordination of market transactions, system-wide transmission planning, and network reliability. e.g., Midwest Independent System Operator (MISO)


Interconnection — The physical connection of a DG facility to the distribution system so that parallel operation can occur.


Interconnection Disconnect Switch — A mechanical device used to disconnect a DG facility from a distribution system. Also known as an isolation device.


Interconnection Guidelines — The means the Wisconsin Distributed Generation Interconnection Guidelines”. The interconnection guidelines are an advisory document for PSC 119 that will be available at the commission and at electric providers in either hard copy or electronic format.


Inverter A machine, device or system that converts direct current power to alternating current power.


Islanding — A condition on the distribution system in which a DG facility delivers power to customers using a portion of the distribution system that is electrically isolated from the remainder of the distribution system.


kV – kilovolt.


kW – kilowatt.


MW – megawatt.


Make-Before-Break — Operational sequence of a transfer switch or relay where the new connection is made prior to disconnecting the existing connection.


Material Modification – Any modification that changes the maximum electrical output of a DG facility or changes the interconnection equipment, including:

a) Changing from certified to non-certified devices.

b) Replacing a component with a component of different functionality or UL listing.


Nationally Recognized Testing Laboratory — Any testing laboratory recognized by the U.S. Department of Labor Occupational Safety and Health Administration’s (OSHA) accreditation program. Note: A list of nationally recognized testing laboratories is available at www.osha.gov/dts/otpca/nrtl/index.html


Net Energy Billing — An arrangement where DG facilities can offset their associated load consumption and are compensated for any extra energy delivered to the electric provider at the rate as specified by their tariff. In Wisconsin only DG facilities using renewable resources with a capacity of 20 kW or less are eligible for net energy billing.


Network Service — Network service means two or more primary distribution feeders electrically connected on the low voltage side of two or more transformers, to form a single power source for any customer.
Parallel Operation — The operation, for longer than 100 milliseconds, of an on-site DG facility while the facility is connected to the energized distribution system.


Paralleling Equipment — The generating and protective equipment system that interfaces and synchronizes a DG facility with the distribution system.


Point of Common Coupling — The point where the electrical conductors of the distribution system are connected to the customer's conductors and where any transfer of electric power between the customer and the distribution system takes place.


Point of Interconnection — The point where the DG facility is electrically connected to the customer’s electrical system.


Protective Function — A function of a DG facility, carried out using hardware and software, designed to prevent unsafe operating conditions from occurring before, during, and after the interconnection to a distribution system.


Public Utility — Defined in s. 196.01(5), Stats.


Qualifying Facility (QF) — Small power production facilities not owned by an electric provider, except hydroelectric located at a new dam or diversion, that utilizes at least 75% biomass, waste, renewable resources, or any combination of these as the primary energy source. There is typically no limitation on the size of the facility for wind, solar, or waste. Other facilities are typically less than 80 MW in size. An exact definition is found in 18 CFR, 292.203(a) of the Federal Energy Regulatory Commission’s Regulations.


Standard Application Form PSC Form 6027 for Category 1 DG facilities or PSC Form 6028 for Categories 2 to 4 DG facilities.


Standard Interconnection Agreement — PSC Form 6029 for Category 1 DG facilities or PSC Form 6030 for Categories 2 to 4 DG facilities. Note: A copy of PSC Forms 6027 to 6030 can be obtained at no charge from your local electric provider or from the Public Service Commission, PO Box 7854, Madison, WI 53707-7854.


Supervisory Control and Data Acquisition (SCADA) — A system of remote control and telemetry used to monitor and control the electric system.


Switchgear — Components for switching, protecting, monitoring and controlling electric power systems.


Synchronize — The process of connecting two previously separated alternating current apparatuses after matching frequency, voltage, phase angles, etc. (e.g., paralleling a generator to the electric system). typically no limitation on the size of the facility for wind, solar, or waste. Other facilities are typically less than 80 MW in size. An exact definition is found in 18 CFR, 292.203(a) of the Federal Energy Regulatory Commission’s Regulations.


Standard Application Form PSC Form 6027 for Category 1 DG facilities or PSC Form 6028 for Categories 2 to 4 DG facilities.


Standard Interconnection Agreement — PSC Form 6029 for Category 1 DG facilities or PSC Form 6030 for Categories 2 to 4 DG facilities. Note: A copy of PSC Forms 6027 to 6030 can be obtained at no charge from your local electric provider or from the Public Service Commission, PO Box 7854, Madison, WI 53707-7854.


Supervisory Control and Data Acquisition (SCADA) — A system of remote control and telemetry used to monitor and control the electric system.


Switchgear — Components for switching, protecting, monitoring and controlling electric power systems.


Synchronize — The process of connecting two previously separated alternating current apparatuses after matching frequency, voltage, phase angles, etc. (e.g., paralleling a generator to the electric system).


Tariff… for interconnection and parallel operation of DG facilities — Document setting out the terms and conditions for interconnection and parallel operation of a DG facility, as approved by the Public Service Commission of Wisconsin.


Telemetry — The transmission of DG operating data using telecommunications techniques.


Transfer Switch — A switch designed so that it will disconnect the load from one power source and reconnect it to another source.


UL — Underwriters Laboratories.


Unit — same as DG facility.


Wheeling — The contracted use of transmission (or less commonly distribution) facilities of one or more entities to transmit electricity for another entity.


Working Day — Defined in s. 227.01(14), WI Stats.



 


One Line Diagram

Sample One Line Diagram, Pg. 30