Emergency Power Systems i4d1n

Generator Code Requirements

Generator Code Requirements  Objectives  Professional responsibilities  Identify what codes apply to generator installations.  Understand the differences between normal, emergency, legally required and optional standby power systems.  Become familiar with NFPA 110 – Standard for Emergency and Standby Power System requirements.

Generator Code Requirements  Professional Responsibilities  Reason for this training.  Project Scenario  Scope

Generator Code Requirements  Scenario

Generator Code Requirements

Generator Code Requirements  Code Review  Multiple code issues with the client’s proposed design.  National Electrical Code Issues  Tap Rule 240.21 – Installed disconnect location would require feeders >10ft long.  Ampacity of tap conductors not less than 1/3 of 2000amps (3 sets of 4/0)

 Article 445.19 Generators Supplying Multiple Loads  A single generator supplying more than one load, or multiple generators operating in parallel, shall be permitted to supply either of the following: » (1) A vertical switchboard with separate sections » (2) Individual enclosures with overcurrent protection tapped from a single conductor for load separation and distribution if a generator is provided with overcurrent protection meeting the requirements of 240.15(A)

 NFPA 110 - Emergency equipment location requirements.

Codes Relating to Emergency Power Systems International and Local Building Codes

NFPA -110 Standard for Emergency and Standby Power Systems

International Fire Code

Emergency Power System Requirements

NFPA -111 Standard on Stored Electrical Energy Emergency and Standby Power Systems

NFPA -101 Life Safety Code

NFPA -70 National Electrical Code

Generator Code Requirements  When is emergency and standby power required?  International Building Code (IBC) - Chapter 27  International Fire Code  NFPA 101: Life Safety Code

 What determines installation and design requirements?  NFPA-70: National Electrical Code  NFPA-110: Standard for Emergency and Standby Power Systems  NFPA-111: Standard on Stored Electrical Energy Emergency and Standby Power Systems

Generator Code Requirements  When is emergency and standby power required?  International Building Code (IBC) - Chapter 27  Emergency Power Required for:     

Group A Occupancies – Voice/Alarm Communications Smoke Control Systems Exit Signs Means of Egress illumination And more….

 Standby Power Required for:     

High Rise Buildings Hazardous materials Elevators when required Smoke proof enclosures And more….

Generator Code Requirements  NFPA 70: National Electrical Code  Describes the design and installation requirements for different defined requirements.  References NFPA-101 Life Safety Code for emergency lighting  References NFPA-110 Standard for Emergency and Standby Power Systems for performance requirements.

 Divides Power Sources into:    

Normal Emergency – Article 700 Legally Required Standby Systems – Article 701 Optional Standby Systems – Article 702

Generator Code Requirements  NFPA 70: National Electrical Code  Article 700 Emergency Systems Definitions:  Emergency Systems – Those systems legally required and classed as emergency by municipal, state, federal or other codes, or by any governmental agency having jurisdiction. These systems are intended to automatically supply illumination, power or both to designated areas and equipment in the event of failure of the normal supply or in the event of accident to elements of a system intended to supply, distribute, and control power and illumination essential for safety to human life.

Generator Code Requirements  NFPA 70: National Electrical Code  Article 701 Legally Required Standby Systems Definition:  Those systems required and so classed as legally required standby by municipal, state, federal, or other codes or by any governmental agency having jurisdiction. These systems are intended to automatically supply power to selected loads (other than those classed as emergency systems) in the event of failure of the normal source.  Examples - heating and refrigeration systems, communications systems, ventilation and smoke removal systems, sewage disposal, lighting systems, and industrial processes, that, when stopped during any interruption of the normal electrical supply, could create hazards or hamper rescue or fire-fighting operations.

Generator Code Requirements  NFPA 70: National Electrical Code  Article 702 Optional Standby Systems Definition:  Those systems intended to supply power to public or private facilities or property where life safety does not depend on the performance of the system. Optional standby systems are intended to supply on-site generated power to selected loads either automatically or manually.  Example - Loads that stopped during any power outage, could cause discomfort, serious interruption of the process, damage to the product or process.

Generator Code Requirements  NFPA 110: Standard for Emergency and Standby Power Systems  Latest Version – 2010  Document Scope:  Performance requirements for emergency and standby power systems providing an alternate source of electrical power to loads in buildings and facilities in the event that the primary power source fails.  Includes power sources, transfer equipment, controls, supervisory equipment, and all related electrical and mechanical auxiliary and accessory equipment needed to supply electrical power to the load terminals of the transfer equipment.  Covers installation, maintenance, operation, and testing requirements as they pertain to the performance of the emergency power supply system (EPSS).

Generator Code Requirements  NFPA 110: Standard for Emergency and Standby Power Systems  Applicability  NFPA 110 applies to new installations of EPSS with the exception of routine maintenance and operational testing, which applies to both new and existing facilities.

 The system, method, or device shall be approved for the intended purpose by the authority having jurisdiction.

Generator Code Requirements  NFPA 110: Standard for Emergency and Standby Power Systems  Definitions:  Emergency Power Supply (EPS) - The source of electric power of the required capacity and quality for an emergency power supply system (EPSS).  Emergency Power Supply System (EPSS) - A complete functioning EPS system coupled to a system of conductors, disconnecting means and overcurrent protective devices, transfer switches, and all control, supervisory, and devices up to and including the load terminals of the transfer equipment needed for the system to operate as a safe and reliable source of electric power.

Generator Code Requirements  Typical Power Supply Systems

Generator Code Requirements  Typical Power Supply Systems

Generator Code Requirements  Typical Power Supply Systems

Generator Code Requirements  NFPA 110: Classification of EPSS  The EPSS shall provide a source of electrical power of required capacity, reliability, and quality to loads for a length of time as specified in Table 4.1(a) and within a specified time following loss or failure of the normal power supply as specified in Table 4.1(b).

 Class: The class defines the minimum time, in hours, for which the EPSS is designed to operate at its rated load without being refueled or recharged.

 Type: The type defines the maximum time, in seconds, that the EPSS will permit the load terminals of the transfer switch to be without acceptable electrical power.

 Level: Two levels of equipment installation, performance and maintenance:  Level 1 systems shall be installed where failure of the equipment to perform could result in loss of human life or serious injuries.  Level 2 systems shall be installed where failure of the EPSS to perform is less critical to human life and safety.

Generator Code Requirements  NFPA 110: Classification of EPSS

Generator Code Requirements  NFPA 110: Classification of EPSS  Example: NFPA 101 Life Safety Code Section 7.9 Emergency Lighting  7.9.2.2 New emergency power systems for emergency lighting shall be at least: Type 10 Class 1.5 Level 1  Example: IBC - Hazardous Materials Mechanical Ventilation, Smoke Control Systems Type 60 Class 2 Level 2

Generator Code Requirements  NFPA 110: Energy Sources  Allowable power sources and requirements.  Energy convertor requirements.  Safety Indications and Shutdowns.

 NFPA 110: Transfer Switch Equipment  Provides construction and feature requirements for transfer switches.  Must be listed for emergency service as a complete factory-assembled and factory tested apparatus.  Source monitoring requirements.  Time delays.

Generator Code Requirements  NFPA 110: Transfer Switch Equipment  Protection requirements.  General – Overcurrent protective devices in the EPSS shall be to optimize selective tripping.  Short Circuit Current – The maximum available short circuit current from both utility source and emergency source shall be evaluated.  Overcurrent devices in EPSS shall be accessible to authorized personnel only.

Generator Code Requirements  NFPA 110: Installation and Environmental Considerations  Establishes minimum requirements and considerations.  Minimizes the probability of equipment or cable failure within the EPSS.  Location:  The EPS shall be installed in a separate room for Level 1 installations.  EPSS equipment can be installed within this room.  Minimum 2-hour fire rating or be located outside the building within a proper enclosure.

 Level 1 EPSS equipment shall not be installed within the same room with the normal service equipment, where the service equipment is rated over 150V to ground and equal or greater than 1000 amperes.

Generator Code Requirements  NFPA 110: Installation and Environmental Considerations  Lighting:  The Level 1 or Level 2 EPS equipment location(s) shall be provided with battery-powered emergency lighting. This requirement shall not apply to units located outdoors in enclosures that do not include walk-in access.  The emergency lighting charging system and the normal service room lighting shall be supplied from the load side of the transfer switch.

 Heating, Cooling, Ventilation  With the EPS running at rated load, ventilation air flow shall be provided to limit the maximum air temperature in the EPS room to the maximum ambient air temperature required by the EPS manufacturer.  With combustion type EPS supplying Level 1 EPSS the ventilation supply and return shall be directly from outside utilizing a 2 hour fire rated air transfer system.  The ambient air temperature in the EPS equip. room or outdoor housing containing Level 1 rotating equipment shall not be less than 40F.

Generator Code Requirements  NFPA 110: Installation and Environmental Considerations  Distribution  Distribution and wiring within the EPSS shall be installed iaw NEC.  Distance between EPS and first overcurrent protective device shall be minimized.  All AC-powered and accessory equipment needed for operation of the EPS shall be supplied by either downstream of the ATS or upstream main EPS overcurrent protection device.

Generator Code Requirements  NFPA 110: Installation and Environmental Considerations  Installation Acceptance  Upon completion of the installation of the EPSS, the EPS shall be tested to ensure conformity to the requirements of the standard with respect to both power output and function.  For new Level 1 installations, the EPSS shall not be considered as meeting this standard until the acceptance tests have been conducted and test requirements met.  The authority having jurisdiction shall be given advance notification of the time at which the acceptance test is to be performed so that the authority can witness the test.  Additional testing information is provided describing the requirement such as run time and loading levels.

Generator Code Requirements  NFPA 110: Routine Maintenance and Operational Testing  Provides required maintenance, operational testing, and documentation for emergency power supply systems.  Testing Requirements:  EPSS shall be inspected weekly and exercised under load at least monthly.  Diesel Generators shall be exercised at least once monthly for a minimum of 30 minutes.  EPS test shall be initiated by using test switches at ATS or opening a normal breaker.  Transfer switches are to be operated monthly.  Level 1 EPSS shall be tested continuously for the lesser of its class or 4 hours at least once per 36 months.  Diesel generator loading shall not be less than 30% of its nameplate for the test.

Generator Code Requirements  Summary  Objectives  Identify what codes apply to generator installations.  Understand the differences between normal, emergency, legally required and optional standby power systems.  Become familiar with NFPA 110 – Standard for Emergency and Standby Power System requirements.

 Questions?  End