Critical Operations Power Systems (COPS)

Informational Note: Text that is followed by a reference in brackets has been extracted from NFPA 1600 -2013, Standard on Disaster/Emergency Management and Business Continuity Programs. Only editorial changes were made to the extracted text to make it consistent with this Code.

Part I. General

  1. Scope. The provisions of this article apply to the instal‐ lation, operation, monitoring, control, and maintenance of the portions of the premises wiring system intended to supply, distribute, and control electricity to designated critical opera‐ tions areas (DCOA) in the event of disruption to elements of the normal system.Critical operations power systems are those systems so classed by municipal, state, federal, or other codes by any governmental agency having jurisdiction or by facility engineer‐ ing documentation establishing the necessity for such a system. These systems include but are not limited to power systems, HVAC, fire alarm, security, communications, and signaling for designated critical operations areas.Informational Note No. 1: Critical operations power systems are generally installed in vital infrastructure facilities that, if destroyed or incapacitated, would disrupt national security, the economy, public health or safety; and where enhanced electrical infrastructure for continuity of operation has been deemed necessary by governmental authority.Informational Note No. 2: For further information on disaster and emergency management, see NFPA 1600 -2013, Standard on Disaster/Emergency Management and Business Continuity Programs.Informational Note No. 3: For further information regarding performance of emergency and standby power systems, see NFPA 110-2013, Standard for Emergency and Standby Power Systems.Informational Note No. 4: For further information regarding performance and maintenance of emergency systems in health care facilities, see NFPA 99-2015, Health Care Facilities Code.Informational Note No. 5: For specification of locations where emergency lighting is considered essential to life safety, see NFPA 101-2015, Life Safety Code, or the applicable building code.Informational Note No. 6: For further information regarding physical security, see NFPA 730-2014, Guide for Premises Security.Informational Note No. 7: Threats to facilities that may require transfer of operation to the critical systems include both natu‐ rally occurring hazards and human-caused events. See alsoA.5.3.2 of NFPA 1600 -2013, Standard on Disaster/Emergency Management and Business Continuity Programs.Informational Note No. 8: See Informative Annex F, Availability and Reliability for Critical Operations Power Systems; and Devel‐ opment and Implementation of Functional Performance Tests (FPTs) for Critical Operations Power Systems.Informational Note No. 9: See Informative Annex G, Supervi‐ sory Control and Data Acquisition (SCADA).
  2. Definitions.

Commissioning. The acceptance testing, integrated system testing, operational tune-up, and start-up testing is the process by which baseline test results verify the proper operation and sequence of operation of electrical equipment, in addition to developing baseline criteria by which future trend analysis can identify equipment deterioration.

Critical Operations Power Systems (COPS). Power systems for facilities or parts of facilities that require continuous operation for the reasons of public safety, emergency management, national security, or business continuity.

Designated Critical Operations Areas (DCOA). Areas within a facility or site designated as requiring critical operations power.

Supervisory Control and Data Acquisition (SCADA). An elec‐ tronic system that provides monitoring and controls for the operation of the critical operations power system. This can include the fire alarm system, security system, control of the HVAC, the start/stop/monitoring of the power supplies and electrical distribution system, annunciation and communica‐ tions equipment to emergency personnel, facility occupants, and remote operators.

  1. Risk Assessment. Risk assessment for critical operations power systems shall be documented and shall be conducted in accordance with 708.4(A) through (C).Informational Note: Chapter 5 of NFPA 1600 -2013, Standard on Disaster/Emergency Management and Business Continuity Programs, provides additional guidance concerning risk assessment and hazard analysis.
    1. Conducting Risk Assessment. In critical operations power systems, risk assessment shall be performed to identify hazards, the likelihood of their occurrence, and the vulnerability of the electrical system to those hazards.
    2. Identification of Hazards. Hazards to be considered at a minimum shall include, but shall not be limited to, the follow‐ ing:
      1. Naturally occurring hazards (geological, meteorological, and biological)
      2. Human-caused events (accidental and intentional) [1600:5.3.2]
    3. Developing Mitigation Strategy. Based on the results of the risk assessment, a strategy shall be developed and imple‐ mented to mitigate the hazards that have not been sufficiently mitigated by the prescriptive requirements of this Code.
  2. Physical Security. Physical security shall be provided for critical operations power systems in accordance with 708.5(A) and (B).
    1. Risk Assessment. Based on the results of the risk assess‐ ment, a strategy for providing physical security for critical oper‐
      ations power systems shall be developed, documented, and implemented.
    2. Restricted Access. Electrical circuits and equipment for critical operations power systems shall be accessible to qualified personnel only.
  3. Testing and Maintenance.
  1. Conduct or Witness Test. The authority having jurisdic‐ tion shall conduct or witness a test of the complete system upon installation and periodically afterward.
  2. Tested Periodically. Systems shall be tested periodically on a schedule acceptable to the authority having jurisdiction to ensure the systems are maintained in proper operating condi‐ tion.
  3. Maintenance. The authority having jurisdiction shall require a documented preventive maintenance program for critical operations power systems.Informational Note: For information concerning maintenance, see NFPA 70B-2013, Recommended Practice for Electrical Equipment Maintenance.
  4. Written Record. A written record shall be kept of such tests and maintenance.
  5. Testing Under Load. Means for testing all critical power systems during maximum anticipated load conditions shall be provided.

Informational Note: For information concerning testing and maintenance of emergency power supply systems (EPSSs) that are also applicable to COPS, see NFPA 110-2013, Standard for Emergency and Standby Power Systems.

708.8 Commissioning.

  1. Commissioning Plan. A commissioning plan shall be developed and documented.Informational Note: For further information on developing a commissioning program see NFPA 70B-2013, Recommended Prac‐ tice for Electrical Equipment Maintenance.
  2. Component and System Tests. The installation of the equipment shall undergo component and system tests to ensure that, when energized, the system will function properly.
  3. Baseline Test Results. A set of baseline test results shall be documented for comparison with future periodic maintenance testing to identify equipment deterioration.
  4. Functional Performance Tests. A functional performance test program shall be established, documented, and executed upon complete installation of the critical system in order to establish a baseline reference for future performance require‐ ments.

Informational Note: See Informative Annex F for more informa‐ tion on developing and implementing a functional performance test program.

Part II. Circuit Wiring and Equipment

  1. Feeder and Branch Circuit Wiring.
    1. Identification.
      1. Boxes and Enclosures. In a building or at a structure where a critical operations power system and any other type ofpower system are present, all boxes and enclosures (including transfer switches, generators, and power panels) for critical operations power system circuits shall be permanently marked so they will be readily identified as a component of the critical operations power system.
      2. Receptacle Identification. In a building in which COPS are present with other types of power systems described in other sections in this article, the cover plates for the receptacles or the receptacles themselves supplied from the COPS shall have a distinctive color or marking so as to be readily identifia‐ ble. Nonlocking-type, 125-volt, 15- and 20-ampere receptacles supplied from the COPS shall have an illuminated face or an indicator light to indicate that there is power to the receptacle.Exception: If the COPS supplies power to a DCOA that is a stand-alone building, receptacle cover plates or the receptacles themselves shall not be required to have distinctive marking.
    2. Wiring. Wiring of two or more COPS circuits supplied from the same source shall be permitted in the same raceway, cable, box, or cabinet. Wiring from a COPS source or COPS source distribution overcurrent protection to critical loads shall be kept entirely independent of all other wiring and equip‐ ment.Exception: Where the COPS feeder is installed in transfer equipment enclosures.
    3. COPS Feeder Wiring Requirements. COPS feeders shall comply with 708.10(C)(1) through (C)(3).
      1. Protection Against Physical Damage. The wiring of the COPS system shall be protected against physical damage. Only the following wiring methods shall be permitted:
        1. Rigid metal conduit, intermediate metal conduit, or Type MI cable.
        2. Where encased in not less than 50 mm (2 in.) of concrete, any of the following wiring methods shall be permitted:
          1. Schedule 40 or Schedule 80 rigid polyvinyl chloride conduit (Type PVC)
          2. Reinforced thermosetting resin conduit (Type RTRC)
          3. Electrical metallic tubing (Type EMT)
          4. Flexible nonmetallic or jacketed metallic raceways
          5. Jacketed metallic cable assemblies listed for installa‐ tion in concrete
        3. Where provisions must be made for flexibility at equip‐ ment connection, one or more of the following shall also be permitted:
          1. Flexible metal fittings
          2. Flexible metal conduit with listed fittings
          3. Liquidtight flexible metal conduit with listed fittings
        (2) Fire Protection for Feeders. Feeders shall meet one of the following conditions:(1) The cable or raceway is protected by a listed electrical circuit protective system with a minimum 2-hour fire rating.image(2) The cable or raceway is a listed fire-resistive cable systemwith a minimum 2-hour fire rating.Informational Note: The listing organization provides informa‐ tion for electrical circuit protection systems on proper installa‐ tion requirements to maintain the fire rating.

        Informational Note No. 1: Fire-resistive cables are tested toANSI/UL 2196, Tests for Fire Resistive Cables.Informational Note No. 2: The listing organization provides information for fire-resistive cable systems on proper installation requirements to maintain the fire rating.(3) The cable or raceway is protected by a listed fire-rated assembly that has a minimum fire rating of 2 hours.(4) The cable or raceway is encased in a minimum of 50 mm (2 in.) of concrete.(3) Floodplain Protection. Where COPS feeders are installed below the level of the 100-year floodplain, the insulated circuit conductors shall be listed for use in a wet location and be installed in a wiring method that is permitted for use in wet locations.
    4. COPS Branch Circuit Wiring.
      1. Outside the DCOA. COPS branch circuits installed outside the DCOA shall comply with the physical and fire protec‐ tion requirements of 708.10(C)(1) through (C)(3).
      2. Within the DCOA. Any of the wiring methods recognized in Chapter 3 of this Code shall be permitted within the DCOA.
  2. Branch Circuit and Feeder Distribution Equipment.
    1. Branch Circuit Distribution Equipment. COPS branch circuit distribution equipment shall be located within the same DCOA as the branch circuits it supplies.
    2. Feeder Distribution Equipment. Equipment for COPS feeder circuits (including transfer equipment, transformers, and panelboards) shall comply with (1) and (2):
    1. Be located in spaces with a 2-hour fire resistance rating
    2. Be located above the 100-year floodplain
  3. Feeders and Branch Circuits Supplied by COPS. Feed‐ ers and branch circuits supplied by the COPS shall supply only equipment specified as required for critical operations use.

708.14 Wiring of HVAC, Fire Alarm, Security, Emergency Communications, and Signaling Systems. All conductors or cables shall be installed using any of the metal wiring methods permitted by 708.10(C)(1) and, in addition, shall comply with 708.14(1) through (8), as applicable.

  1. All cables for fire alarm, security, signaling systems, and emergency communications shall be shielded twisted pair cables or installed to comply with the performance requirements of the system.
  2. Shields of cables for fire alarm, security, signaling systems, and emergency communications shall be arranged in accordance with the manufacturer’s published installa‐ tion instructions.
  3. Optical fiber cables shall be used for connections between two or more buildings on the property and under single management.
  4. A listed primary protector shall be provided on all communications circuits. Listed secondary protectors shall be provided at the terminals of the communications circuits.
  5. Conductors for all control circuits rated above 50 volts shall be rated not less than 600 volts.
  6. Communications, fire alarm, and signaling circuits shall use relays with contact ratings that exceed circuit voltage and current ratings in the controlled circuit.
  7. All cables for fire alarm, security, and signaling systems shall be riser-rated and shall be a listed 2-hour electrical circuit protective system. Emergency communication cables shall be Type CMR-CI or shall be riser-rated and shall be a listed 2-hour electrical circuit protective system.
  8. Control, monitoring, and power wiring to HVAC systems shall be a listed 2-hour electrical circuit protective system.

Part III. Power Sources and Connection

  1. Sources of Power.
    1. General Requirements. Current supply shall be such that, in the event of failure of the normal supply to the DCOA, criti‐ cal operations power shall be available within the time required for the application. The supply system for critical operations power, in addition to the normal services to the building and meeting the general requirements of this section, shall be one or more of the types of systems described in 708.20(E) through (H).Informational Note: Assignment of degree of reliability of the recognized critical operations power system depends on the careful evaluation in accordance with the risk assessment.
    2. Fire Protection. Where located within a building, equip‐ ment for sources of power as described in 708.20(E) through
    (H) shall be installed either in spaces fully protected by approved automatic fire suppression systems (sprinklers, carbon dioxide systems, and so forth) or in spaces with a 2-hour fire rating.
    1. Grounding. All sources of power shall be grounded as a separately derived source in accordance with 250.30.Exception: Where the equipment containing the main bonding jumper or system bonding jumper for the normal source and the feeder wiring to the transfer equipment are installed in accordance with 708.10(C) and 708.11(B).
    2. Surge Protection Devices. Surge protection devices shall be provided at all facility distribution voltage levels.
    3. Storage Battery. An automatic battery charging means shall be provided. Batteries shall be compatible with the charger for that particular installation. Automotive-type batter‐ ies shall not be used.
    4. Generator Set.
      1. Prime Mover-Driven. Generator sets driven by a prime mover shall be provided with means for automatically starting the prime mover on failure of the normal service. A time-delay feature permitting a minimum 15-minute setting shall be provi‐ ded to avoid retransfer in case of short-time reestablishment of the normal source.
      2. Power for fuel transfer pumps. Where power is needed for the operation of the fuel transfer pumps to deliver fuel to a generator set day tank, this pump shall be connected to the COPS.
      3. Dual Supplies. Prime movers shall not be solely depend‐ ent on a public utility gas system for their fuel supply or munic‐ ipal water supply for their cooling systems. Means shall be provided for automatically transferring from one fuel supply to another where dual fuel supplies are used.
      4. Battery Power and Dampers. Where a storage battery is used for control or signal power or as the means of starting the prime mover, it shall be suitable for the purpose and shall be equipped with an automatic charging means independent of the generator set. Where the battery charger is required for the operation of the generator set, it shall be connected to the COPS. Where power is required for the operation of dampers used to ventilate the generator set, the dampers shall be connected to the COPS.
      5. Outdoor Generator Sets.
        1. Permanently Installed Generators and Portable Generators Greater Than 15 kW. Where an outdoor housed generator set is equipped with a readily accessible disconnecting means in accordance with 445.18, and the disconnecting means is loca‐ ted within sight of the building or structure supplied, an addi‐ tional disconnecting means shall not be required where ungrounded conductors serve or pass through the building or structure. Where the generator supply conductors terminate at a disconnecting means in or on a building or structure, the disconnecting means shall meet the requirements of 225.36.
        2. Portable Generators 15 kW or Less. Where a portable generator, rated 15 kW or less, is installed using a flanged inlet or other cord-and plug-type connection, a disconnecting means shall not be required where ungrounded conductors serve or pass through a building or structure.
      6. Means for Connecting Portable or Vehicle-Mounted Gener‐ ator. Where the COPS is supplied by a single generator, a means to connect a portable or vehicle-mounted generator shall be provided.
      7. On-Site Fuel Supply. Where internal combustion engines are used as the prime mover, an on-site fuel supply shall be provided. The on-site fuel supply shall be secured and protec‐ ted in accordance with the risk assessment.
    5. Uninterruptible Power Supplies. Uninterruptible power supplies used as the sole source of power for COPS shall comply with the applicable provisions of 708.20(E) and (F).
    6. Fuel Cell System. Installation of a fuel cell system shall meet the requirements of Parts II through VIII of Article 692.
  2. Ventilation. Adequate ventilation shall be provided for the alternate power source for continued operation under maximum anticipated ambient temperatures.Informational Note: NFPA 110-2013, Standard for Emergency and Standby Power Systems, and NFPA 111-2013, Standard on Stored Energy Emergency and Standby Power Systems, include additional information on ventilation air for combustion and cooling.
  3. Capacity of Power Sources.
  1. Capacity and Rating. A COPS shall have capacity and rating for all loads to be operated simultaneously for continu‐ ous operation with variable load for an unlimited number of hours, except for required maintenance of the power source. A portable, temporary, or redundant alternate power source shall be available for use whenever the COPS power source is out of service for maintenance or repair.
  2. Selective Load Pickup, Load Shedding, and Peak Load Shaving. The alternate power source shall be permitted to supply COPS emergency, legally required standby, and optional loads where the source has adequate capacity or where auto‐ matic selective load pickup and load shedding is provided as needed to ensure adequate power to (1) the COPS and emer‐gency circuits, (2) the legally required standby circuits, and(3) the optional standby circuits, in that order of priority. The alternate power source shall be permitted to be used for peak load shaving, provided these conditions are met.Peak load-shaving operation shall be permitted for satisfying the test requirement of 708.6(B), provided all other conditions of 708.6 are met.
  3. Duration of COPS Operation. The alternate power source shall be capable of operating the COPS for a minimum of 72 hours at full load of DCOA with a steady-state voltage within ±10 percent of nominal utilization voltage.

708.24 Transfer Equipment.

  1. General. Transfer equipment, including automatic trans‐ fer switches, shall be automatic and identified for emergency use. Transfer equipment shall be designed and installed to prevent the inadvertent interconnection of normal and critical operations sources of supply in any operation of the transfer equipment. Transfer equipment and electric power production systems installed to permit operation in parallel with the normal source shall meet the requirements of Article 705.
  2. Bypass Isolation Switches. Means shall be permitted to bypass and isolate the transfer equipment. Where bypass isola‐ tion switches are used, inadvertent parallel operation shall be avoided.
  3. Automatic Transfer Switches. Where used with sources that are not inherently synchronized, automatic transfer switches shall comply with (C)(1) and (C)(2).
    1. Automatic transfer switches shall be listed for emergency use.
    2. Automatic transfer switches shall be electrically operated and mechanically held.
  4. Use. Transfer equipment shall supply only COPS loads.imageN
  5. Documentation. The short-circuit current rating of the transfer equipment, based on the specific overcurrent protec‐ tive device type and settings protecting the transfer equipment, shall be field marked on the exterior of the transfer equip‐ ment.

708.30 Branch Circuits Supplied by COPS. Branch circuits supplied by the COPS shall only supply equipment specified as required for critical operations use.

Part IV. Overcurrent Protection

708.50 Accessibility. The feeder- and branch-circuit overcur‐ rent devices shall be accessible to authorized persons only.

708.52 Ground-Fault Protection of Equipment.

  1. Applicability. The requirements of 708.52 shall apply to critical operations (including multiple occupancy buildings) with critical operation areas.
  2. Feeders. Where ground-fault protection is provided for operation of the service disconnecting means or feeder discon‐ necting means as specified by 230.95 or 215.10, an additional step of ground-fault protection shall be provided in all next level feeder disconnecting means downstream toward the load. Such protection shall consist of overcurrent devices and708.52 ARTICLE 712 — DIRECT CURRENT MICROGRIDS
    current transformers or other equivalent protective equipment that causes the feeder disconnecting means to open.•
  3. Testing. When equipment ground-fault protection is firstinstalled, each level shall be tested to ensure that ground-fault protection is operational.Informational Note: Testing is intended to verify the ground- fault function is operational. The performance test is not inten‐ ded to verify selectivity in 708.52(D), as this is often coordinated similarly to circuit breakers by reviewing time and current curves and properly setting the equipment. (Selectivity of fuses and circuit breakers is not performance tested for overload and short circuit.)
  4. Selectivity. Ground-fault protection for operation of the service and feeder disconnecting means shall be fully selective such that the feeder device, but not the service device, shall open on ground faults on the load side of the feeder device. Separation of ground-fault protection time-current characteris‐ tics shall conform to the manufacturer’s recommendations and shall consider all required tolerances and disconnect operating time to achieve 100 percent selectivity.

Informational Note: See 230.95, Informational Note No. 4, for transfer of alternate source where ground-fault protection is applied.

708.54 Selective Coordination. Critical operations power system(s) overcurrent devices shall be selectively coordinated with all supply-side overcurrent protective devices.

Selective coordination shall be selected by a licensed profes‐ sional engineer or other qualified persons engaged primarily in the design, installation, or maintenance of electrical systems. The selection shall be documented and made available to those authorized to design, install, inspect, maintain, and operate the system.

Exception: Selective coordination shall not be required between two over‐ current devices located in series if no loads are connected in parallel with the downstream device.

Part V. System Performance and Analysis

708.64 Emergency Operations Plan. A facility with a COPS shall have documented an emergency operations plan. The plan shall consider emergency operations and response, recov‐ ery, and continuity of operations.

Informational Note: NFPA 1600 -2013, Standard on Disaster/Emer‐ gency Management and Business Continuity Programs, Section 5.7, provides guidance for the development and implementation of emergency plans.