New Publication ©1989

S&C ELECTRIC COMPANY

PHOTO SHEET 911-705Page 1 of 4

October 16, 1989

S&C Cypoxy® Insulators Station Post InsulatorsIndoor and Outdoor Distribution4.8 kV through 34.5 kV

The newly constructed substation pictured below, locatedin the southwestern United States, features the exclusiveuse of S&C’s Cypoxy station post insulators for bussupport on the 25-kV secondary buswork grid. The instal-lation, in addition, features an extensive selection of S&Cswitch and fuse products supplied with Cypoxy stationpost insulators—including thirty-nine S&C LoadbusterDisconnects, four S&C SMD-20 Power Fuses, three S&CRegulator Bypass Switches, and an integer style S&CAlduti-Rupter Switch. All together, the substationincludes one hundred forty-two Cypoxy station postinsulators.

The Decision to Adopt CypoxyA number of factors contributed to this electric utility’sdecision to construct a nearly all Cypoxy substation. Thetrim profile and aesthetics of S&C Cypoxy insulators,coupled with the shorter lead time relative to porcelaininsulators played an important role in the selection ofCypoxy. However, of even greater importance were theoutstanding electrical and mechanical-strength character-istics of Cypoxy insulators.

Figure 1. Distribution substation in southwestern United States featuring more than one hundred forty Cypoxy station postinsulators for apparatus and bus-support applications.

Cypoxy Station Post InsulatorsSet a New Standard in Substation High-Voltage Insulation

S&C Cypoxy® Insulators Station Post InsulatorsIndoor and Outdoor Distribution4.8 kV through 34.5 kV

The Cypoxy AdvantageS&C Cypoxy insulators are of molded construction, incor-porating a uniquely formulated cycloaliphatic epoxy resinespecially tailored to provide the electrical and mechani-cal-strength characteristics required of high-voltage insu-lators. Full-scale tests, including exhaustive outdoor test-ing at desert and seacoast test facilities that press thelimit in ultraviolet radiation and salt-spray exposure foran insulator, document the outstanding performance ofCypoxy insulators across a broad range of environments.And, verification of Cypoxy-insulator performance is fur-ther augmented by more than 15 years’ actual experiencewith Cypoxy insulators applied worldwide. In addition tothese performance characteristics, S&C Cypoxy stationpost insulators are electrically and mechanically inter-changeable with porcelain station post insulators—andthey meet or exceed the electrical and mechanical-strength ratings established in ANSI Standard C29.9(1983) for porcelain standard-strength insulators.

Other advantages of Cypoxy station post insulatorsinclude a light-weight design that is approximately onehalf the weight of comparable porcelain insulators . . . butwith even greater dry arcing and leakage distances.

S&C Cypoxy insulators are also formulated to resistdamage from power arcs such as may result from bridgingby a snake or other animal. Laboratory tests documentthe ability of Cypoxy insulators to withstand power arcsat currents to 25,000 amperes RMS symmetrical—withoutdamage—and to maintain rated electrical capabilitieswithout any need for post-arc cleanup. Porcelain insula-tors may be damaged by thermal shock and requirereplacement in the event of a high-current arc across theinsulator skirts.

And finally, Cypoxy insulators are homogeneous anddo not include a surface glaze. As a consequence, Cypoxyinsulators are tougher than porcelain with regard tomechanical shock. And even if a Cypoxy insulator shouldbe damaged, for example, by loss of a skirt due to vandal-

Figure 2. . . . another view of substation showing the extensive application of S&C’s Cypoxy station post insulators.

911-705 PHOTO SHEETPage 2 of 4October 16, 1989

ism, the insulator will retain rated capabilities due to itshomogeneous construction. Porcelain insulators may suf-fer substantial reductions in strength as a result of dam-age to the glaze or to the insulator skirts.

Field- and Test-Proven PerformanceS&C has been engaged in the production of Cypoxy insu-lators for more than 15 years . . . with more than 2¹⁄₄ mil-lion insulator units shipped in that period. Extensive real-time and accelerated-life testing at desert, seacoast, andurban installations—plus long-term application in actualservice—confirm Cypoxy’s reliability for outdoor applica-tions.

Cypoxy insulators offer significant advantages in termsof cost, capabilities, and aesthetics that can be providedwith a wide selection of S&C distribution switch and fuseproducts. For more information concerning S&C Cypoxy

insulators, or products furnished with Cypoxy insulators,consult your nearest S&C Sales Office.

Figure 3. Cypoxy station post insulator rated 34.5 kV.

PHOTO SHEET 911-705Page 3 of 4

October 16, 1989

S&C Cypoxy® Insulators Station Post InsulatorsIndoor and Outdoor Distribution4.8 kV through 34.5 kV

S&C ELECTRIC COMPANY

911-705 PHOTO SHEETPage 4 of 4October 16, 1989

Prin

ted

in U

.S.A

.

The versatility of Cypoxy . . .

. . . for switches. . . . for fuse mountings and bus support.

. . . for disconnects.