Westinghouse and Cutler Hammer Load Break Switches — a Brief History

Westinghouse started making load break switches in 1950. Popular switches were 5–15 kV. The early switches were called load break fusible (LBF). Westinghouse made the next generation of switches, Westinghouse load interrupters (WLI), though 1980. Cutler Hammer also made load interrupters. Cutler Hammer now makes medium-voltage switchgear (MVS). It is available in voltages of 5–15 kV and 38 kV. Circuit Breakers Sales NE, Inc. stocks these different generations of switches.

ITE Load Break Switches — a Brief History

ITE started making load break switches after World War II. The most popular voltages were 5 kV and 15 kV. ITE load break switches were called HPLC switches. The came fused and non-fused and were produced for more than 30 years. ITE, BBC, and Gould all manufactured HPLC switches. ABB produced its own load break switch, called the ABB Versa Switch, which had a limited run from the mid-1970s to 1980. This switch came in standard ratings of 5 kV, 15 kV, and 38 kV.

GE Load Break Switches — a Brief History

Between 1945 and 2000, GE built most of the switchgear in the United States. GE’s most popular switch was the SE-100S. SE stood for “stored energy,” and the switch came in many different configurations. GE load break switches came with indoor (NEMA 1) or outdoor (NEMA 3r) enclosures. The switches were either fused or non-fused.

Replacement Parts

Circuit Breaker Sales NE stocks replacement parts for load break switches. The most commonly needed parts are 5 kV and 15 kV fuses, to be used as spares or replacements. Many manufactures place a pocket in the front door of the switch to hold spare fuses.

Different manufacturers’ switches tend to need different replacement parts, since each design has its own weak points. For example, “whipper blades” tend to break on GE SE-100S switches. A small contact often comes off as the blade whips into the arc chute. Cutler Hammer load break switches often require mechanism parts, as torque put on the mech during closing sometimes breaks key parts. Handle assemblies and porcelain push rods often break on ITE HPLC load break switches. Glastic push rods on the ABB Versa Switch often need replacing. Circuit Breaker Sales NE stocks all these different parts, and load break switches too.