2006 AREMA Technical Conference. A Systems Approach. Jeff Kleoppel

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2 2006 AREMA Technical Conference AREMA Recommended Practices for Electrical Surge Protection A Systems Approach Jeff Kleoppel

3 Abstract: AREMA Recommended Practices, a Systems Approach to Surge Protection!

4 AREMA Committee AREMA Committee C38 is responsible for the Surge Protection Guidelines and Recommended Practices. Mr. Peter Brackett Mr. Bill Scheerer Chairman Vice Chairman

5 AREMA Surge Protection Standards: 1. MP Recommended General Practices for Electrical Surge Protection of Signal Systems 2. MP Recommended Guidelines for Signal Enclosure Layout, Component Placement and General Wiring Strategies for Surge Damage Prevention 3. MP Recommended Design Criteria for Surge Withstand Capability of Electronic Signal Equipment for Signal Systems 4. MP Recommended Instructions for Application of Electrical Surge Protection for Signal Systems

6 AREMA Surge Protection Standards: 5. MP Recommended Design Criteria and Functional/ Operating Guidelines for Primary Surge Protectors 6. MP Recommended Design Criteria and Functional/ Operating Guidelines for Secondary Surge Protectors. 7. MP Recommended Design Criteria for Copper Clad Steel Ground Rods and connections for Signal Systems 8. MP Recommended Design Criteria for Chemically Enhanced Ground Electrode Systems for Signal Systems 9. MP Purpose and Meaning of Terms Used in Surge Protection and Grounding. 10. MP Recommended Instructions for Made Grounds for Signal Systems Utilizing Earth Electrodes.

7 A Systems View of Surge Protection

8 Fundamental Elements of a Surge Protection System Wiring Surge Protection Devices AREMA Compliant Equipment Fundamental Elements of a Surge Protection System Enclosure Layout Low Impedance Reference

9 Which Element is Most Important? All of them!!!

10 A Quote from AREMA The best engineered surge protection plan will be defeated if the installation and wiring methods are not implemented with surge protection in mind. In particular, it is critical that surge protected wiring be kept separate from non-protected wiring.

11 A Quote from AREMA Proper installation and wiring of surge protection devices and protected equipment is of equal importance to the operation of the surge protectors themselves

12 Recommended Practices Element by Element

13 Wiring Practices Wiring Surge Protection Devices AREMA Compliant Equipment Fundamental Elements of a Surge Protection System Enclosure Layout Low Impedance Reference

14 Wiring Practices Physically Separate Clean and Dirty Wires to minimize coupling AC Power wiring shall be enclosed in metallic conduit DC Power wires shall be twisted, short as possible, and separated from Dirty Wires. DC Bus for the equipment shall be connected directly to the Battery and not to the Charger

15 Example Poor Wire Separation Clean Wires Large Parallel Coupling Area Dirty Wires

16 Example Better Wire Separation Clean Wires Smaller Perpendicular Coupling Area Dirty Wires

17 DC Power Wiring AC Battery Charger Battery Bank Equipment DC Bus Twisted Pairs

18 Enclosure Layout W irin g Surge Protection D evices AREMA C o m p lia n t Equipm ent Fundam ental Elem ents of a Surge Protection System Enclosure Layout Low Im pedance Reference

19 Signal Enclosure Layout Locate equipment to facilitate clean and dirty wire separation Locate the primary Surge Protection Devices (SPDs) as close to the entrance of the external wires as possible Locate Secondary / Tertiary Protection at the Equipment

20 Enclosure Layout Example AC Primary Protection RF Primary Protection Clean Wires Equipment External Wire Primary Protection

21 Surge Protection Devices W ir in g S u r g e Protection D e v ic e s A R E M A C o m p lia n t Equipm ent Fundam ental Elem ents of a Surge Protection System Enclosure Layout Low Im pedance R eference

22 Surge Protection Devices Staged Levels of Protection Line to Line and Line to Ground Protection Arrange Primary Protection Devices to allow a low impedance connection to the reference plane Use the right device for the job

23 Surge Protection Devices Example Equipment Enclosure Protected Equipment Line In Primary Protection (Line - GND) Secondary Protection (Line - Line) Tertiary Protection (Line - Line) Low Impedance Reference (metallic skin of bungalow) Circuit Common

24 Low Impedance Reference W ir in g S u r g e Protection D evices A R E M A C om pliant Equipm ent F u n d a m e n t a l Elem ents o f a Surge Protection System Enclosure Layout Low Im pedance R e fe r e n c e

25 Low Impedance Reference Provide a Low Impedance Reference for the Surge Protection System The Metallic Skin of the enclosure can be used as the Low Impedance Reference Bond the ground terminal of the Primary Arrestors to the Low Impedance Reference

26 Effects of Impedance in the Reference Surge Current through Equipment Equipment Enclosure Line In Protected Equipment Battery In Impedance in Reference Primary Protection Primary Protection Increased voltage across Equipment Low Impedance Reference

27 Increased Impedance due Series Straps Wire to Bungalow Skin Significant Impedance in this path to the ground wire

28 Reduced Impedance Scheme Lower Impedance with multiple wide conductors

29 AREMA Compliant Equipment W ir in g S u r g e Protection D evices A R E M A C o m p lia n t Equipm ent Fundam ental Elem ents of a Surge Protection System Enclosure Layout Low Im pedance R eference

30 AREMA Compliant Equipment Equipment must withstand the Let Through levels of the Primary Protection Equipment shall incorporate Isolation Impedance Equipment must Survive, and Ride Through or Self Recover following a surge

31 AREMA Compliant Equipment Example Equipment Enclosure Line In Isolation Impedance Protected Equipment Primary Protection Secondary Protection Low Impedance Reference (metallic skin of bungalow eventually Earth Ground) Circuit Common

32 In Conclusion Successful Surge Protection Requires a SYSTEMS APPROACH including 5 Fundamental Elements: 1. Proper Wiring Practices 2. Proper Signal Enclosure Layout 3. Proper Surge Protection Devices 4. AREMA Compliant Equipment 5. Low Impedance Reference for Surge Current

33 Acknowledgements Mr. Bill Scheerer GE Mr. Forrest Ballinger GE Mr. Dave Gove Transtector

34 Questions?