DOE Handbook
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3.0 ELECTRICAL PREVENTIVE MAINTENANCE The term "electrical preventive maintenance" (EPM) refers to a program of regular inspection and service of equipment to detect potential problems and to take proper corrective measures through the approved work process controls. 3.1 DEVELOPMENT AND IMPLEMENTATION REQUIREMENTS An EPM program should be developed and implemented based on the requirements of: 1. DOE O 433.1, Maintenance Management Program for DOE Nuclear Facilities (2001) 2. NFPA 70B, Recommended Practice for Electrical Equipment Maintenance (2002)
3. NFPA 70E, Standard for Standard for Electrical Safety in the Workplace (2004) 4. NFPA 72, National Fire Alarm Code (2002) 5. National Electrical Testing Association (1997) 6. ANSI-C2, National Electrical Safety Code (2002) 3.2 DEFINITION An EPM program is defined as the system that manages the conducting of routine inspections and tests and the servicing of electrical equipment so that impending troubles can be detected and reduced or eliminated. Where designers, installers, or constructors specify, install, and construct equipment with optional auxiliary equipment, that optional equipment should be part of the EPM program. Records of all inspections, tests, and servicing should be documented and reviewed.
All electrical equipment that is appropriate for EPM should be inspected, tested, and serviced in accordance with an EPM program. Inspections, tests, and servicing shall be performed by personnel who are qualified for the work to be performed. These qualifications can be shown by appropriate documentation of work experience, on-the-job, and offsite formal training to verify understanding and retention of minimum knowledge, skills, and abilities. 3.3 MAINTENANCE Electrical equipment should be maintained in accordance with the manufacturer's recommendations and instructions for the local operating environment. A copy of the manufacturer's recommendations should be documented and on file. 3.4 INSPECTION If an EPM program does not exist, an inspection, testing, and servicing program should be developed and implemented to establish a baseline to initiate an EPM program. The inspection
frequency should be as recommended by the manufacturer or as otherwise indicated in NFPA 70B. An initial period of inspection (sometimes several years) provides sufficient knowledge that, when accumulated, may permit increasing or decreasing that interval based upon documented observations and experience.
One guidance on how to determine inspection frequency is described in various sections of NFPA 70B, Tables H.1, H.2, and I.1 including, but not limited to, the following sections: 1. Inspection Frequency for Planning and Developing an Electrical Preventive Maintenance Program 2. Recommended Frequency for Substations 3. Frequency of Maintenance for Switchgear Assemblies 4. Regular Inspections and Special Inspections and Repairs for Liquid-Filled Transformers 5. Regular Inspections and Special Inspections and Repairs for Dry-Type Transformers 6. Visual Inspection Intervals for Power Cables 7. Frequency of Inspections for Enclosures of Motor Control Centers
8. Recommended Frequency for Ground-Fault Circuit Interrupters
9. General and Inspection and Cleaning for High-Voltage Fuses
10. Frequency for Rotating Equipment 11. Cleaning Interval for Lighting Equipment 12. Visual Inspection Before and After Each Use, Periodic Inspection of Crucial Wear Points, Excessive Dirt Accumulation, Insufficient or Improper Lubrication, and Visually Inspected Before Each Use for Portable Electric Tools and Equipment 13. Special Maintenance Tests, Frequency of Tests, Inspection Frequency and Procedures, and Insulating-Liquid Analysis for Testing and Test Methods 14. Reinspection and Retesting Within One or Two Years After Energization for General Aspects of Maintaining Medium- and Low-Voltage Distribution Systems, Frequency, Regreasing, and Frequency for Lubrication of Rotating Equipment 15. Inspections Should Be Made of All New Installations and Whenever Alterations Are Made and; Recordkeeping for Electrostatics Static Grounding (see NFPA 77) 16. Inspection and Testing of Power Supplies, Functional Systems Testing of Interlock and Logic Systems, Visual Inspection of Level Devices, Frequency of Testing Safety and Shutdown Systems, Frequency of Testing Alarm Systems, and Visual Checking of Wiring Systems for Process Instrumentation and Control 17. Frequency for Cable Tray System
18. Routine Maintenance for Uninterruptible Power Supply (UPS) Systems
3.5 ESSENTIAL ELEMENTS The EPM program should include the essential elements described in NFPA 70B, Chapter 5, What is an Effective EPM Program?. This includes planning, identifying the main parts, and utilizing available support services for a program. For example:
1. Assigning qualified personnel 2. Surveying and analyzing equipment maintenance requirements 3. Performing routine inspections and tests 4. Analyzing inspection and test reports 5. Prescribing corrective measures 6. Performing necessary work 7. Preparing appropriate records. 3.6 PLANNING AND DEVELOPING AN EPM PROGRAM, AND FUNDAMENTALS OF EPM The EPM program should be planned and developed to include each of the functions, requirements, and economic considerations described in NFPA 70B, Chapter 6, Planning and Developing an EPM Program, and NFPA 70B, Chapter 7, Fundamentals of EPM. Chapter 6 includes surveying the existing electrical system installation, identifying crucial equipment, establishing a systematic program to follow, and developing methods and procedures to plan, analyze, perform, verify, and record. Electrical drawings should be kept current. A system of recording changes in electrical systems and then integrating those changes into the applicable drawings should be developed and implemented. NFPA 70B includes designing to accommodate maintenance, scheduling maintenance, personnel and equipment safety, circuit protection, and initial acceptance testing.
3.7 GROUND-FAULT PROTECTION The EPM program should include the essential ingredients of Chapter 14 of NFPA 70B, Ground Fault Protection. This includes GFCIs and ground-fault protection for equipment (GFPE). Ground-fault protective devices are intended to protect personnel and equipment. There are two distinct types — GFCI and GFPE — and it is extremely important to understand the difference between them. A GFCI is defined in Article 100 of the NEC as a device intended for the protection of personnel in their job assignments. (See NEC 210.8, 215.9, 427, 527)
A GFPE is defined in Article 100 of the NEC as a system intended to provide protection of equipment from line-to-ground fault currents. GFPE systems (equipped with or without a test panel) shall be inspected and tested at installation and at specified intervals as recommended by the manufacturer. Figure 3-1 shows a zero-sequence type of ground fault protection.
Figure 3-1. Ground-fault protection shall be provided with 277/480-V, three-phase, four-wire services with over current protection devices of 1,000 A or more. A ground fault sensor (window) can be used to encircle all service conductors, including the grounded conductor (neutral). Inspections, tests, and servicing shall be performed by personnel who are qualified for the work to be performed. These qualifications can be shown by appropriate documentation of work experience, on-the-job, and offsite formal training to verify understanding and retention of minimum knowledge, skills, and abilities.
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