AN OVER VIEW PRESENTATION FOR Engineers, Architects & Electrical Professionals

1. UL STANDARD 1449 (3rdEdition) AN OVER VIEW PRESENTATION FOR Engineers, Architects & Electrical Professionals

2. ONE STANDARD… ANSI/UL Standard 1449 (3rd Edition) Replaces: UL 1449 (2.5) TVSS & OWHX Secondary Surge Arresters NEW PRODUCT NOMENCLATURE IS SPD (SURGE PROTECTIVE DEVICE) Effective: September 2009

4. NRTLs NRTLs are third-party organizations recognized by OSHA as having the capability to provide product safety testing and certification services to the manufacturers of a wide range of products for use in the American workplace. The testing and certifications are based on product safety standards developed by U.S.-based standards developing organizations and often issued by the American National Standards Institute (ANSI).

5. Language in OSHA Regulations Requiring “Approval” OSHA regulations require certain equipment and materials to be… • Accepted • Approved • Certified • Listed • Meet the requirements of • Otherwise determined to be safe • Tested and approved • Tested and listed

6. Product Safety Standards Accepted for NRTLs Standards of the following organizations have been accepted for NRTLs: • American National Standards Institute (ANSI) • American Society for Testing and Materials (ASTM) • Underwriters Laboratories (UL) • Factory Mutual Research Corporation (FMRC)

7. NRTL Program History and Background • When first adopted, OSHA regulations gave two examples of approval organizations: Underwriters Laboratories (UL) and Factory Mutual Research Corporation (FMRC) • In 1983, OSHA was ordered by a court to remove the specific references to UL and FMRC in a successful lawsuit brought by a private lab • In 1988, OSHA revised its regulations to remove the references, and established the NRTL Program to recognize other organizations as NRTLs

8. NRTLs - Examples and Certification Marks • See http://www.osha.gov/dts/otpca/nrtl/nrtlmrk.html

9. NATIONAL ELECTRIC CODE… The 2008 NEC (NFPA 70) already includes updates to Articles 280 and 285 to reflect the changes of ANSI/UL1449 3rd Edition.

10. PROTECTOR VS APPLICATION? • IEEE category C - High exposure • IEEE category B - Medium exposure • IEEE category A - Low exposure

11. TYPE DESIGNATIONS: For installation between secondary of the service transformer and the line side of the service entrance overcurrent device. SPDs are permanently connected and installed without external overcurrent protection. Type 1: For installation on the load side of the service entrance overcurrent device. SPDs are permanently connected and can be use at branch panel locations. Type 2 Point-of –Use SPDs to be installed with a minimum conductor length of 10 meters (30 ft) from the electrical service panel to point of utilization. Type 3 Component SPDs for installation in other enclosures at any of the above locations… Type 4

12. EXPOSURE LEVELS… • IEEE category C - 20kV/10kA • IEEE category B - 6kV/3kA • IEEE category A - 6kV/500A

13. VPR vs SVR… VPR = 3rd Edition (Voltage Protection Rating) SVR = 2.5 Edition (Surge Voltage Rating) KeyTek E Class Surge Generator 3kA Current wave (8x20µs) 500A SVR Saved in Reference 1 – Then A 3kA VPR Current Wave was Obtained for Comparison. 3kA is 6 times the current of 0.5kA dumping approximately 36 times more energy into the SPD (I2R) 500A Current wave (8x20µs) CT used has a ratio of 0.005V/A, therefore 2.5V = 500A and 15V = 3000A.

14. Let through Voltages… VPR = 3rd Edition (Voltage Protection Rating) SVR = 2.5 Edition (Surge Voltage Rating) KeyTek E Class Surge Generator 3kA VPR Voltage Wave 500A SVR Saved in M Reference Then A 3kA VPR Current Wave was Obtained for Comparison. 3kA Clamp = 1552V 500A Clamp = 1352V 0.5kA VPR Voltage Wave Voltages measured in accordance with UL 1449 2nd and 3rd Edition Standards. 550V MOVs Typically used In 480VAC Applications

15. In Testing • 20kA - Type 1 ? • 10kA - Type 2 ? • 3kA - Type 3 ?

16. 1449 (3rdEdition) In Testing 37.7 Nominal discharge current – For Type 1 and Type 2 SPDs 37.7.1 The manufacturer shall specify (declare) the value of the Nominal Discharge Current (In) to which the sample will be tested. The value of the Nominal Discharge Current (In) selected by the manufacturer shall be: 10 kA or 20 kA for Type 1 SPDs and 3 kA, 5 kA, 10 kA or 20 kA for Type 2 SPDs. The surge generator shall be adjusted to ensure that the value of In (selected by the manufacturer) is impressed through the SPD. 37.7.2 Type 1 and Type 2 SPDs and Type 4 SPDs (intended for use in locations where Type 1 and Type 2 SPDs are installed), shall be subjected to the Nominal Discharge Current (In) Test as specified in Table 37.1. The same three representative devices that were subjected to the 6 kV/3 kA combination wave in the Voltage Protection Rating Test, shall then be subjected to fifteen (15) x 8/20 short circuit current surges, per mode. The surges are to be applied at the application points specified in 37.4. 37.7.3 During the application of these surges the samples are unenergized. Surges shall be applied in three groups of five surges. Within 1 second after the application of each surge, the manufacturer’s specified (declared) MCOV shall be applied for 60 seconds ±15 seconds. After each group of 5 surges, the sample shall rest for 30 minutes ±5 minutes. After the 15th surge, the MCOV shall be re-applied for at least 15 minutes. Exception: After each group of 5 surges, the sample may rest for less than 30 minutes if agreeable to all concerned.

17. Comparison of 20kA and 10kA In M-Ti High Energy Surge Generator 20kA 8x20µs Current Wave 10kA wave Saved in Reference 2 Then A 20kA wave was Obtained for Comparison. 10kA 8x20µs Current Wave CT used has a ratio of 1000A/V, therefore 10V = 10kA and 20V = 20kA. 20kA dumps about 4 times the energy into the SPD over a 10kA wave. I2R

18. In Pass Criteria 37.8.3 Pass Criteria – During and following the Nominal Discharge Current Test and the Duty Cycle Test, the following conditions shall not result: a) Emission of flame, molten metal, glowing or flaming particles through any openings preexisting or created as a result of the test) in the product. b) Charring, glowing, or flaming of the supporting surface, tissue paper, or cheesecloth. c) Ignition of the enclosure. d) Creation of any openings in the enclosure that results in accessibility of live parts, when judged in accordance with Accessibility of Live Parts, Section 13. e) Supplementary protective devices, internal or external to the SPD, opening.

19. Symmetrical Fault Current 39.2.3 The Short Circuit Current Rating Test Circuit is shown in Figure 39.1. The Short Circuit Current Ratings Tables are shown in Tables 39.2 and 39.3. Table 39.2 Short-circuit current ratings (SCCR) selection table – rms symmetrical current in amperes 5000 10,000 14,000 18,000 22,000 25,000 30,000 42,000 50,000 65,000 85,000 100,000 125,000 150,000 200,000

20. IEEE Standard C62 IEEE Std C62.72TM-2007 IEEE Guide for the Application of Surge-Protective Devices for Low-Voltage (1000 V or Less) AC Power Circuits. For Type 1 Locations Neutral And Ground Are BONDED.

21. SPD LOCATION OR APPLICATION Switchgear Locations Secondary Or Subpanel Locations Flashover Levels? Arc Flash?

22. Example of a Type 1 Installation SPD or TVSS

23. SPD kA Ratings… How much protection is enough and is there such a thing as to much? kA/mode or phase?

24. END Information provided in this presentation courtesy of OSHA, UL, IEEE, NEC and ETL Intertek