INSULATORS 101 PRESENTED BY ANDY SCHWALM PRESIDENT VICTOR

“INSULATORS 101” PRESENTED BY ANDY SCHWALM PRESIDENT – VICTOR INSULATORS, INC. IEEE LIFE MEMBER PRESENTED TO: SWEDE MAY 8, 2014 - SAN ANTONIO, TX

WHO DEVELOPED INSULATORS 101? § INSULATOR WORKING GROUP 15. 09 OF THE (THEN) L&I SUBCOMMITTEE – NOW OHL SUBCOMMITTEE • TONY BAKER – VICE PRESIDENT – TECHNOLOGY – K-LINE INSULATORS USA • AL BERNSTORF – PRINCIPAL ENGINEER – INSULATORS – HUBBELL POWER SYSTEMS • TOM GRISHAM – CONSULTANT – GRISCUT LTD • ANDY SCHWALM – PRESIDENT – VICTOR INSULATORS, INC.

WHAT IS AN INSULATOR? WHAT DOES IT DO ? § AN INSULATOR IS A “DAM***” § MAINTAINS AN AIR GAP POOR CONDUCTOR! AND MORE, TECHNICALLY SPEAKING! § AN INSULATOR IS A MECHANICAL SUPPORT! § PRIMARY FUNCTION - SUPPORT THE “LINE” MECHANICALLY § SECONDARY FUNCTION– ELECTRICAL § AIR IS THE INSULATOR § OUTER SHELLS/SURFACES ARE DESIGNED TO INCREASE LEAKAGE DISTANCE AND STRIKE § SEPARATES LINE FROM GROUND § LENGTH OF AIR GAP DEPENDS PRIMARILY ON SYSTEM VOLTAGE, MODIFIED BY DESIRED SAFETY MARGIN, CONTAMINATION, ETC. § RESISTS MECHANICAL STRESSES § “EVERYDAY” LOADS, EXTREME LOADS § RESISTS ELECTRICAL STRESSES § SYSTEM VOLTAGE/FIELDS, OVERVOLTAGES § RESISTS ENVIRONMENTAL

HISTORY • WHERE DID INSULATORS COME FROM? BASICALLY GREW OUT OF THE NEEDS OF THE TELEGRAPH INDUSTRY – STARTING IN THE LATE 1700 S, EARLY 1800 S • HISTORY FROM APPROX. 1840 TO PRESENT GLASS PLATES USED TO INSULATE TELEGRAPH LINE DC TO BALTIMORE • TYPES OF INSULATORS DISTRIBUTION, TRANSMISSION, SUBSTATION, PORCELAIN, GLASS, NCI, CYCLOALIPHATIC, HDPE ETC. • COMPARISON OF TYPES (MATERIALS) THE “PLUS AND MINUS” OF THE MULTITUDE OF DESIGNS AND MATERIALS IN USE TODAY

INSULATOR TYPES - COMPARISONS • CERAMIC • PORCELAIN OR TOUGHENED GLASS • METAL COMPONENTS FIXED WITH CEMENT • ANSI STANDARDS C 29. 1 THROUGH C 29. 10 • NON CERAMIC • TYPICALLY FIBERGLASS ROD WITH RUBBER (EPDM OR SILICONE) SHEATH AND WEATHER SHEDS • HDPE LINE INSULATOR APPLICATIONS • CYCLOALIPHATIC (EPOXIES) STATION APPLICATIONS, SOME LINE APPLICATIONS • METAL COMPONENTS NORMALLY CRIMPED • ANSI STANDARDS C 29. 11 – C 29. 19

INSULATOR TYPES - COMPARISONS • CERAMIC • NON CERAMIC • MATERIALS VERY RESISTANT TO UV, CONTAMINANT DEGRADATION, ELECTRIC FIELD DEGRADATION • HYDROPHOBIC MATERIALS IMPROVE CONTAMINATION PERFORMANCE • MATERIALS STRONG IN COMPRESSION, WEAKER IN TENSION • STRONG IN TENSION, WEAKER IN COMPRESSION • DEFLECTION UNDER LOAD CAN BE AN ISSUE • HIGH MODULUS OF ELASTICITY - STIFF • LIGHTER – EASIER TO HANDLE • BRITTLE, REQUIRE MORE CAREFUL HANDLING • ELECTRIC FIELD STRESSES MUST BE CONSIDERED • HEAVIER THAN NCIS

INSULATOR TYPES - COMPARISONS • CERAMIC • GENERALLY DESIGNS ARE “MATURE” • LIMITED FLEXIBILITY OF DIMENSIONS • PROCESS LIMITATIONS ON SIZES AND SHAPES • APPLICATIONS/HANDLING METHODS GENERALLY WELL UNDERSTOOD • NON CERAMIC • “MATERIAL PROPERTIES • • HAVE BEEN IMPROVED – UV RESISTANCE MUCH IMPROVED FOR EXAMPLE STANDARDIZED PRODUCT LINES NOW EXIST BALANCING ACT - LEAKAGE DISTANCE/FIELD STRESS – TAKE ADVANTAGE OF HYDROPHOBICITY APPLICATION PARAMETERS STILL BEING DEVELOPED LINE DESIGN IMPLICATIONS (LIGHTER WEIGHT, IMPROVED SHOCK RESISTANCE)

DESIGN CRITERIA - MECHANICAL • AN INSULATOR IS A MECHANICAL SUPPORT! ITS PRIMARY FUNCTION IS TO SUPPORT THE LINE MECHANICALLY ELECTRICAL CHARACTERISTICS ARE AN AFTERTHOUGHT WILL THE INSULATOR SUPPORT YOUR LINE? DETERMINE THE MAXIMUM LOAD THE INSULATOR WILL EVER SEE - INCLUDING NESC OVERLOAD FACTORS.

DESIGN CRITERIA - MECHANICAL • LINE POST INSULATORS • PORCELAIN • CANTILEVER RATING • REPRESENTS THE AVERAGE ULTIMATE STRENGTH IN CANTILEVER – WHEN NEW. • MINIMUM ULTIMATE CANTILEVER OF A SINGLE UNIT MAY BE AS LOW AS 85%. • NEVER EXCEED 40% OF THE CANTILEVER RATING – PROOF TEST LOAD • NCIS (POLYMER INSULATORS) • S. C. L. (SPECIFIED CANTILEVER LOAD) • NOT BASED UPON LOT TESTING • BASED UPON MANUFACTURER TESTING • R. C. L. (REFERENCE CANTILEVER LOAD) OR MDCL (MAXIMUM DESIGN CANTILEVER LOAD) OR MCWL OR WCL (WORKING CANTILEVER LOAD) • NEVER EXCEED RCL OR MDCL OR MCWL OR WCL • S. T. L. (SPECIFIED TENSILE LOAD) • TENSILE PROOF TEST=(STL/2)

DESIGN CRITERIA - MECHANICAL • SUSPENSION INSULATORS • PORCELAIN • M&E (MECHANICAL & ELECTRICAL) RATING • REPRESENTS A MECHANICAL TEST OF THE UNIT WHILE ENERGIZED. • WHEN THE PORCELAIN BEGINS TO CRACK, IT ELECTRICALLY PUNCTURES. • AVERAGE ULTIMATE STRENGTH WILL EXCEED THE M&E RATING WHEN NEW. • NEVER EXCEED 50% OF THE M&E RATING • NCIS (POLYMER INSULATORS) • S. M. L. – SPECIFIED MECHANICAL LOAD • GUARANTEED MINIMUM ULTIMATE STRENGTH WHEN NEW. • R. T. L. – ROUTINE TEST LOAD – PROOF TEST APPLIED TO EACH NCI. • NEVER LOAD BEYOND THE R. T. L.

DESIGN CRITERIA - ELECTRICAL • DESIGN CRITERIA - ELECTRICAL FOCUS ON THE IMPORTANCE OF STRIKE DISTANCE AS THE PRIMARY CHARACTERISTIC FOR DETERMINING ELECTRICAL PROPERTIES, WITH CONSIDERATION GIVEN TO LEAKAGE (CREEPAGE) • STRIKE AND LEAKAGE • DRY 60 HZ F/O AND IMPULSE F/O – BASED ON STRIKE DISTANCE. • WET 60 HZ F/O - SOME WOULD ARGUE LEAKAGE DISTANCE AS A PRINCIPAL FACTOR. AT THE EXTREMES THAT ARGUMENT FAILS – ALTHOUGH IT DOES PLAY A ROLE. • LEAKAGE DISTANCE HELPS TO MAINTAIN THE SURFACE

DESIGN CRITERIA – ELECTRICAL WHAT’S AN APPROPRIATE LEAKAGE DISTANCE? “Application Guide for Insulators in a Contaminated Environment” by K. C. Holte et al – F 77 639 -8 ESDD (mg/cm 2) 0 – 0. 03 – 0. 06 Site Severity Very Light Leakage Distance I-string/Vstring (“/k. V l-g) IEC 60815 Standards ESDD (mg/cm 2) Site Severity Leakage Distance (“/k. V l-g) <0. 01 Very Light 0. 87 0. 01 – 0. 04 Light 1. 09 0. 04 – 0. 15 Medium 1. 37 0. 15 – 0. 40 Heavy 1. 70 >0. 40 Very Heavy 2. 11 0. 94/0. 8 1. 18/0. 97 0. 06 – 0. 1 Moderate 1. 34/1. 05 >0. 1 Heavy 1. 59/1. 19

DESIGN CRITERIA – ELECTRICAL WHAT’S AN APPROPRIATE LEAKAGE DISTANCE?

DESIGN CRITERIA - ELECTRICAL • IMPULSE WITHSTAND IF ONLY CRITICAL IMPULSE FLASHOVER IS AVAILABLE – ASSUME 90% (TAKE POSITIVE OR NEGATIVE POLARITY, WHICHEVER IS LOWER SAFE ESTIMATE FOR WITHSTAND) • IMPORTANCE OF CORONA (GRADING) RINGS

INSULATOR ELECTRICAL RATINGS Dry 60 Hz Flashover Data 1400 1200 Suspension Insulator Flashover (k. V) 1000 800 Station Post and Line Post 600 400 200 0 0 20 40 60 80 100 Dry Arcing Distance (inches) 120 140 160

STANDARDS • FOCUS ON ANSI STANDARDS • REVIEW OF MECHANICAL AND ELECTRICAL RATINGS • ANALYSIS OF RATINGS VS. DESIGN FOR IN SERVICE LOAD REQUIREMENTS

STANDARDS C 29 ANSI C 29 Insulator Standards (available on-line at nema. org) . 1 Insulator Test Methods . 2 Wet-process Porcelain & Toughened Glass - Suspensions . 3 Wet-process Porcelain Insulators - Spool Type . 4 “ - Strain Type . 5 “ - Low & Medium Voltage Pin Type . 6 “ - High Voltage Pin Type . 7 “ - High Voltage Line Post Type . 8 “ - Apparatus, Cap & Pin Type . 9 “ - Apparatus, Post Type . 10 “ - Indoor Apparatus Type . 11 Composite Insulators – Test Methods . 12 “ - Suspension Type . 13 “ - Distribution Deadend Type . 17 “ - Line Post Type . 18 “ - Distribution Line Post Type . 19 “ - Station Post Type (under development)

STANDARDS • ANSI STANDARDS APPLY TO NEW INSULATORS AND COVER: • DEFINITIONS • MATERIALS • DIMENSIONS & MARKING (INTERCHANGEABILITY) • TESTS 1. PROTOTYPE & DESIGN, USUALLY PERFORMED ONCE FOR A GIVEN DESIGN. (DESIGN, MATERIALS, MANUFACTURING PROCESS, AND TECHNOLOGY). 2. SAMPLE, PERFORMED ON RANDOM SAMPLES FROM LOT OFFERED FOR ACCEPTANCE. 3. ROUTINE, PERFORMED ON EACH INSULATOR TO ELIMINATE DEFECTS FROM LOT.

STANDARDS STD. No. C 29. 2 Insulator Type Ceramic Suspension Sample test Routine test M&E Tension C 29. 3, C 29. 4 Ceramic Spools and Strains Tension None C 29. 5 Pin Type Puncture Electrical C 29. 6 “ Pin Type Cantilever Electrical C 29. 7 “ Line Post Cantilever 4 quad. cantilever C 29. 8 “ Cap & Pin Cantilever, T, To Tension Station Post Cantilever, T or BM C 29. 9 “ C 29. 10 Indoor Apparatus Cantilever Electrical C 29. 12 Composite Suspension SML Tension C 29. 13 “ Deadend SML Tension C 29. 17 “ Line Post Cantilever, T Tension C 29. 18 “ Dist. Line Post Cantilever Tension

STANDARDS – NEW C 29. 2 A AND C 29. 2 B • FOR TRANSMISSION CLASSES (C 29. 2 B) NOW TWO RATINGS CLASS FOR EACH “LEVEL” • E. G. PREVIOUSLY ONLY CLASS 52 -3 • NOW: 52 -3 L AND 52 -3 H

STANDARDS – NEW C 29. 2 Dimensional Values ANSI Class 52 -3 -L 52 -3 -H Connectio n type Clevis 52 -4 -H Clevis 52 -5 -L 52 -5 H B&S Type J 52 -6 -L Clevis 52 -6 -H Clevis 52 -8 -L 52 -8 -H B&S Type K 52 -10 -L Clevis 52 -10 -H Clevis 52 -11 B&S Type K 52 -12 Clevis 11 -1/2 (292) 11 (279) 11 (279) 15 (381) 5 -3/4 (146) 5 -3/4 (146) 5 -3/4 (146) 6 -1/2 (165) 6 -1/8 (155. 5) 7 (178) 10 -3/4 (273) 10 -3/4 (273) 11 -3/4 (298) 12 -1/4 (311) 15, 000 (67) 20, 000 (89) 25, 000 (111) 30, 000 (133) 36, 000 (160) 40, 000 (178) 50, 000 (222) 55 (6. 0) 60 (7. 0) 90 (10) 90 (10) 7, 500 (33. 5) 10, 000 (44. 5) 12, 500 (55. 5) 15, 000 (66. 5) 18, 000 (80) 20, 000 (89) 25, 000 (111) Radio-influence Voltage Maxim Critical Lowum RIV impulse frequency frequenc at flashover, puncture y test 1, 000 positive, negative, voltage, k. Hz, k. V µV Electrical Values Impact Low. Leakage Shell M&E Tension strength, frequenc Spacing, distance, diameter, strength, proof, inches inchy dry inches pounds (mm) pounds flashover, (mm) (k. N) (N-m) k. V B&S Type B 52 -4 -L Mechanical Values Lowfrequency wet flashover, k. V 80 50 125 130 110 10 50 80 50 125 130 110 10 50 80 50 125 130 110 10 50 80 50 140 140 125 10 50

STANDARDS – NEW C 29. 2 COMBINED MECHANICAL AND ELECTRICAL-STRENGTH TEST TEN ASSEMBLED INSULATORS SHALL BE SELECTED AT RANDOM FROM THE LOT AND TESTED IN ACCORDANCE WITH 5. 2 OF ANSI C 29. 1. THE CRITERIA FOR DETERMINING CONFORMANCE WITH THE STANDARD ARE AS FOLLOWS: ALL INSULATORS SUBJECTED TO THE COMBINED MECHANICAL AND ELECTRICAL-STRENGTH TEST SHALL EQUAL OR EXCEED THE RATED COMBINED MECHANICAL AND ELECTRICAL STRENGTHS AS GIVEN IN TABLE 2 OF THIS STANDARD.

STANDARDS – IMPLICATIONS EXAMPLE C 29. 2 M&E TEST Coefficient of variation, v. R Strength value at -3σ 5% 90% of M&E rating 10% 79% of M&E rating 15% 67% of M&E rating

STANDARDS – IMPLICATIONS EXAMPLE C 29. 7, 8, 9 CANTILEVER TEST Coefficient of variation, v. R Strength value at -3 σ 5% 85% of Cantilever rating 10% 70% of Cantilever rating 15% 55% of Cantilever rating

NESC ANSI C 2 TABLE 277 -1 ALLOWED PERCENTAGES OF STRENGTH RATINGS Insulator Type % Strength Rating 2 Ref. ANSI Std. C 29. 2 -1992 C 29. 7 -1996 40% 50% Combined mechanical & electrical strength (M&E) Cantilever strength Tension/compression Strength Cantilever strength Tension/compression/torsion strength C 29. 9 -1983 C 29. 8 -1985 50% Specified mechanical load (SML) C 29. 12 -1997 C 29. 13 -2000 50% Specified cantilever load (SCL) or specified tension load (STL) All strength ratings C 29. 17 -2002 C 29. 18 -2003 Ceramic 3 Suspension Line Post Station Post 4 Station Cap & Pin 4 Nonceramic 5 Suspension Line Post Station Post 50% 40% 50% -----

STRENGTHS – MORE IN DEPTH DISCUSSION 2 NEW IEEE PAPERS • IEEE TF ON INSULATOR LOADING, “HIGH VOLTAGE INSULATORS MECHANICAL LOAD LIMITS –PART I: OVERHEAD LINE LOAD AND STRENGTH REQUIREMENTS, ” IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 27, NO. 3, JULY 2012 • IEEE TF ON INSULATOR LOADING, “HIGH VOLTAGE INSULATORS MECHANICAL LOAD LIMITS –PART II: STANDARDS AND RECOMMENDATIONS, ” IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 27, NO. 4, OCTOBER 2012.

INSPECTION & EVALUATION – HAVE THE INSULATORS DETERIORATED IN SERVICE?

INSPECTION & EVALUATION – HAVE THE INSULATORS DETERIORATED IN SERVICE?

SOURCES

DOMESTIC MANUFACTURING • TRANSMISSION • DISTRIBUTION § PORCELAIN, GLASS – NONE § NCIS – FULL LINES § PORCELAIN – ONLY 1 PLANT LEFT § GLASS – NONE § NCIS- FULL LINES (CHANGING) • PORCELAIN: • SUBSTATION § CUT OUT PORCELAIN – NONE § PORCELAIN – FULL LINES (FOR NOW) § NCIS- FULL LINES (CHANGING) § SPOOLS, STRAINS – NONE § LINE POSTS – MIXED § PIN TYPES – 1 PLANT

MARKET SIZE DATE TOTAL LVPOST HVPOST LVSUSP HV SUSP STATION SALES SALES 2005 $162, 659, 854 $9, 175, 541 $50, 689, 720 $21, 321, 445 $37, 249, 650 $44, 223, 498 2006 $186, 134, 838 $8, 764, 774 $56, 879, 248 $21, 326, 689 $42, 944, 457 $54, 341, 020 2007 $178, 871, 136 $8, 148, 902 $54, 370, 706 $19, 123, 333 $41, 294, 116 $55, 934, 079 2008 $184, 703, 067 $9, 033, 449 $55, 328, 125 $20, 249, 198 $45, 963, 460 $54, 128, 835 2009 $199, 346, 541 $7, 212, 093 $55, 796, 547 $16, 462, 470 $64, 840, 398 $50, 381, 412 2010 $204, 434, 456 $5, 631, 635 $57, 686, 263 $19, 853, 611 $57, 254, 895 $64, 008, 052 2011 $265, 809, 282 $8, 490, 867 $82, 247, 066 $21, 663, 012 $78, 483, 176 $74, 925, 161 2012 $275, 534, 244 $8, 761, 597 $81, 904, 852 $21, 427, 918 $91, 549, 038 $71, 890, 839

MARKET DISTRIBUTIONS • DISTRIBUTION – STILL MAINLY PORCELAIN BELOW 35 KV, EXCEPT FOR DEAD ENDS – 90% NCI, GROWING USE OF HDPE • TRANSMISSION – MAINLY NCI BELOW 345 KV, >50% CERAMIC ABOVE THAT

ECONOMICS • TRANSMISSION LINES – INSULATORS TYPICALLY <3% TOTAL COST OF LINE • DISTRIBUTION LINES – INSULATORS TYPICALLY 1% - 3% OF COST OF LINE

INSPECTION & EVALUATION – INSPECTION TECHNIQUES AND EVALUATION OF RESULTS • VISUAL INSPECTION • INDIVIDUAL INSULATORS FROM A BUCKET TRUCK OR HELICOPTER • BINOCULAR ASSIST • VIDEO IMAGING • DAYTIME (DAYCOR) • NIGHT TIME (THERMAL IMAGING) • EVALUATING CORONA ACTIVITY • RIV MEASUREMENTS • ESTABLISHED BASIS OF GOOD AND BAD • REPLACEMENT OF INSULATORS • DO NOT “HOT” WORK ANY LINE WITH KNOWN FAILURES. • PROCEDURES TO WORK “HOT” LINES IS NO DIFFERENT FOR CERAMIC OR NCI’S. • SELECT A RANDOM SAMPLE, N= 30. • SUBJECT TO M&E TEST AND DETERMINE � 30 & S • WOULD LIKE (� 30 – KS) ≥ M&E RATING • USE STUDENT’S T STATISTIC • FOR Α =. 05 (95% CONFIDENCE), WANT T≥ 1. 699. k Want � 30 ≥ 1 M&E + 1. 31 s 2 M&E + 2. 31 s 3 M&E + 3. 31 s