Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations

Upstream Segment

API RECOMMENDED PRACTICE 14F FIFTH EDITION, JULY 2008

Special Notes

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Copyright © 2008 American Petroleum Institute

Foreword

This recommended practice (RP) contains information for use primarily by engineers with a working knowledge of electrical systems and production operations. Some of the information may be useful to experienced electrical maintenance and operating personnel. The intent of the document is to identify important features of offshore electrical systems and to present generally accepted practices for electrical design and installation that experience in the offshore petroleum industry has shown results in safe, reliable, efficient, and maintainable operations. Nothing in this RP is to be construed as a fixed rule without regard to sound engineering judgment, nor is it intended to supersede or override any federal, state, or local regulation where applicable.

The First Edition of API 14F was published in July 1978 as API 14F, Design and Installation of Electrical Systems for Offshore Production Platforms, under the jurisdiction of the API Production Department. The Second Edition was published on July 1, 1985. The Third Edition was published September 1, 1991. The Fourth Edition was published June 1999, with a new title, Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Division 1 and Division 2 Locations. A related document, API 14FZ, Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1 and Zone 2 Locations, was published in 1999 to address wiring methods introduced in Article 505 of the 1999 National Electrical Code.

This document includes usage of the verbs shall and should; whichever is the more applicable to the function. For the purpose of this document:

Shall indicates the RP is considered a minimum requirement that has universal applicability to the specific activity.

Should indicates a RP: (1) for which alternative practices may be equally safe and/or effective; or, (2) which may not be practical under some circumstances or applications.

It is recommended indicates a preferred practice that has no known direct safety or regulatory implication.

Phrases that use “consider” such as “should be considered,” “consideration should be given,” etc, indicate the user should pay particular attention to the referenced topic, in the context of the sentence where used as well as other related topics in this document and then make an application decision based on the relevant facts and sound engineering judgment.

This RP shall become effective on the date printed on the cover but may be used voluntarily from the date of distribution.

API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any federal, state, or municipal regulation with which this publication may conflict.

Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.

This document was produced under API standardization procedures that ensure appropriate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this publication or comments and questions concerning the procedures under which this publication was developed should be directed in writing to the Director of Standards, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the director.

Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-time extension of up to two years may be added to this review cycle. Status of the publication can be ascertained from the API Standards Department, telephone (202) 682-8000. A catalog of API publications and materials is published annually and updated quarterly by API, 1220 L Street, N.W., Washington, D.C. 20005.

Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW, Washington, D.C. 20005, standards@api.org.

Contents

Page

1. General 1

   1. Scope 1

   2. Applicability of National Electrical Code 1

2. References 1

   1. Industry Codes, Guides, and Standards 1

   2. Government Codes, Rules, and Regulations 9

   3. Classification Society Rules and Regulations 10

3. Acronyms and Abbreviated Definitions 11

   1. Acronyms 11

   2. Definitions, Abbreviated 12

   3. Definitions Specific to Floating Facilities 26

4. Electrical Equipment for Hazardous (Classified) Locations 27

   1. General 27

   2. High-temperature Devices 28

   3. Protection Techniques Related To Equipment Installed in Locations Classified

      as Division 1 or Division 2 28

   4. Protection Techniques Related to Equipment Approved for Zone 0, Zone 1, or Zone 2 Locations 31

   5. General Purpose Equipment 31

   6. Listing, Marking and Documentation 31

5. Electric Power Generating Stations 32

   1. General 32

   2. Prime Movers 32

   3. Generators 36

   4. Generator Packaging Considerations 42

   5. Switchboards 42

   6. Special Requirements for Floating Facilities 44

6. Electrical Distribution Systems 47

   1. Scope 47

   2. Voltage Level Selection 47

   3. Conductor Selection 48

   4. Wiring Methods for Classified Locations 55

   5. Wiring Methods for Unclassified Locations 60

   6. Wiring Methods for Drilling and Workover Rigs 60

   7. General Wiring Considerations 60

   8. Conduit and Cable Seals and Sealing Methods 64

   9. Circuit Protection. 74

   10. Grounding 74

   11. Electrical Enclosures 77

   12. Working Space About Electrical Equipment and Means of Access 82

   13. Additional Requirements for Floating Facilities 84

7. Electric Motors 84

   1. General 84

   2. Selection 84

   3. Motor Space Heaters 86

   4. Motor Control 86

      v

8. Transformers 88

   1. General 88

   2. Selection 88

   3. Installation 90

   4. Connections 90

   5. Protection 91

9. Lighting 92

   1. General 92

   2. Lighting Levels 92

   3. Fixture Selection and Installation 93

   4. Standby Lighting 95

   5. Lighting for Helicopter Operations 96

10. Battery-powered DC Supply Systems 97

    1. General 97

    2. Specific Applications 98

    3. Batteries 98

    4. Battery Chargers 102

    5. Uninterruptible Power Supply (UPS) Systems 103

11. Special Systems 105

    1. Electrical Platform Safety Control Systems 105

    2. Gas Detection Systems 107

    3. Fire Detection Systems 108

    4. Aids-to-Navigation Equipment 109

    5. Communications Equipment 110

    6. Heat Trace Systems 111

    7. Fire Pumps 111

    8. Adjustable Frequency Controllers (Variable Frequency Drives) 111

    9. Submarine Cables 118

    10. Electric Oil-immersion Heaters 118

    11. Electric Power-operated Boat Winches for Survival Craft 119

    12. Electric Power-operated Water-tight Doors 119

    13. Hull Mechanical Systems Controls 119

    14. Cargo Tanks on Floating Facilities 119

    15. Cargo Handling Rooms on Floating Facilities 120

    16. General Alarm System 120

    17. Cathodic Protection 123

12. Special Considerations 124

    1. Construction Practices 124

    2. Electronic Instrumentation 126

    3. Electrical Tools 126

    4. Electrical Appliances 126

    5. Extension Cords. 127

    6. Electrical Equipment Buildings 127

    7. Signs 127

    8. Lockout and Tagout Procedures 127

    9. Portable Electronic Devices 127

13. System Checkout 127

    1. General 127

    2. Generators and Motors 128

    3. Instrumentation and Control Circuits 128

14. Maintenance 128

15. Safety 128

Annex A (informative) Inspection Intervals 129

Annex B (informative) ABS Rules For Building and Classing Steel Vessels—1998, PART 4 131

Annex C (informative) USCG Requirements, 46 CFR, Subchapter J, 111.95 141

Annex D (informative) USCG Requirements, 46 CFR, Subchapter J, 111.97 144

Annex E (informative) USCG Requirements, 46 CFR, Subchapter J, Subpart 111.105 146

Figures

1. Typical Class 1, Division 1 Electrical Installation Conduit System 65

2. Typical Class 1, Division 1 Electrical Installation Cable System 66

3. Typical Class 1, Division 2 Electrical Installation Conduit or Cable System 67

4. Typical Class 1, Division 1 or Division 2 Electrical Installation Conduit and Cable Connections

   to Process-connected Nonarcing Devices with Single-seal Diaphragm or Tube 68

5. Typical Class 1, Division 1 or Division 2 Electrical Installation Conduit and Cable Connections

   to Process-connected Nonarcing Devices with Multiple Seal Diaphragms or Tubes 69

6. Typical Class 1, Division 1 or Division 2 Electrical Installation Conduit or Cable Connections

   to Process-connected Arcing Devices 70

7. Typical Class 1, Division 1 or Division 2 Electrical Installation Placement of Drain Seals 71

8. Typical Speed Torque Curve for Variable Torque Load 114

9. Typical Speed Torque Curve for Constant Torque Load 114

10. Typical Speed Torque Curve for Constant Horsepower Load 115

11. Typical Speed Torque Characteristics for Impact-type Loads 116

4/5 C.1 Limiting Curves for Loading 4-stroke Diesel Engines Step by Step from No-load to

Rated Power as Function of the Brake Mean Effective Pressure 137

Tables

1. Ampacities for Marine Shipboard Distribution, Control, and Signal Cables, 2000 Volts or Less, AC or DC, Copper Conductors, Single-banked (Single-layered), Maximum Current-carrying

   Capacity Based on 45 °C Ambient 49

2. Ampacities for Marine Shipboard Single-conductor Distribution Cables, 2000 Volts or Less DC Only, Copper Conductors, Single-banked (Single-layered), Maximum Current-carrying

   CapacityBased on 45 °C Ambient 50

3. Ampacities for Three-conductor Medium Voltage Power Cable, 2001 Volts to 35 kV, Copper Conductor Single-banked (Single-layered), Maximum Current-carrying Capacity

   Based on 45 °C Ambient 51

4. Ampacities for Medium Voltage Power Cable, 2001 Volts to 35 kV, Copper Conductor Single-conductor in Triplexed or Triangular Configuration, Maximum Current-carrying

   Capacity Based on 45 °C Ambient 52

5. Ampacities for Single-conductor Medium Voltage Power Cable, 2001 Volts to 35 kV, Copper Conductor Single-banked (Single-layered), Maximum Current-carrying Capacity Based

   on 45 °C Ambient, Shields Grounded on One End (Open-circuited Shields) 53

6. Wiring Methods for Classified Locations (See 6.4, 6.6, 6.7, and 6.8 for Explanations

   and Qualifications) 56

7. Common Power and Control Cables Sizes and Configurations 63

8. Common Instrumentation Cable Sizes and Configurations 64

9. Circuit Protection Devices—Advantages and Disadvantages 75

10. NEMA Enclosures 78

11. Degree of Protection of Enclosures in Accordance with IEC 60529 81

    
    

12. Selection of IP Rated enclosures to meet NEMA requirements 81

    12-1 Selection of NEMA enclosures to Meet IP Designations 82

13. Working Clearances 83

14. NEMA Motor Starter Sizing 87

15. Minimum Recommended Levels of Illumination for Efficient Visual Tasks 92

16. Minimum Recommended Levels of Illumination for Safety 93

17. Comparison of Batteries by Cell Type 100

Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1,

Division 1 and Division 2 Locations

1. General

   1. Scope

      
      

      1. This document recommends minimum requirements and guidelines for the design, installation, and maintenance of electrical systems on fixed and floating petroleum facilities located offshore. For facilities classified as Zone 0, Zone 1 or Zone 2, reference API 14FZ, Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1 or Zone 2. These facilities include drilling, producing and pipeline transportation facilities associated with oil and gas exploration and production. This recommended practice (RP) is not applicable to Mobile Offshore Drilling Units (MODUs) without production facilities. This document is intended to bring together in one place a brief description of basic desirable electrical practices for offshore electrical systems. The recommended practices contained herein recognize that special electrical considerations exist for offshore petroleum facilities. These include:

         
         

         1. the inherent electrical shock possibility presented by the marine environment and steel decks;

            
            

         2. space limitations that require that equipment be installed in or near classified locations;

            
            

         3. the corrosive marine environment;

            
            

         4. motion and buoyancy concerns associated with floating facilities.

         
         

      2. This RP applies to both permanent and temporary electrical installations. The guidelines presented herein should provide a high level of electrical safety when used in conjunction with well-defined area classifications. This RP emphasizes safe practices for classified locations on offshore petroleum facilities but does not include guidelines for classification of areas; for guidance on the classification of areas refer to API 500 and API 505, as applicable.

         
         

         1.2 Applicability of National Electrical Code

         
         

         1.2.1 Electrical systems for offshore petroleum facilities shall be designed and installed in accordance with the

         National Electrical Code, 2008 edition, except where specific departures are noted.

         
         

2. References

   1. Industry Codes, Guides, and Standards

Various organizations have developed numerous codes, guides and standards that have substantial acceptance by industry and governmental bodies. Codes, guides, and standards useful in the design and installation of electrical systems are listed below as references only. These are not considered to be a part of this RP except for those specific sections of documents referenced elsewhere in this RP.

API RP 2L, Planning, Designing, and Constructing Heliports for Fixed Offshore Platforms

API RP 14C, Analysis, Design, Installation and Testing of Basic Surface Safety Systems on Offshore Production Platforms

API RP 14FZ, Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1 and Zone 2 Locations

API RP 14G, Fire Prevention and Control on Open Type Offshore Production Platforms

1