Westinghouse Breakers Handbook

About Westinghouse

Westinghouse Electric was founded in 1886 by George Westinghouse Jr. The company played a significant role in the development of electrical engineering technology. It was also a major competitor against Thomas Edison’s electric company.

Westinghouse Electric developed electrical infrastructure throughout the early nineteenth century. It was so successful in its endeavors the company employed 50,000 people by 1900. Westinghouse had factories in Pittsburgh, Pennsylvania and Hamilton, Ontario, where the company manufactured turbines, generators, motors and switch gears. It also funded a formal research and development department where Nikola Tesla perfected his AC induction motor.

The Westinghouse Electric Company went through many difficulties throughout the century. In 1995, it purchased the CBS broadcasting station and became the CBS Corporation in 1997. Even though the company has ceased as a manufacturer of electrical components, many of its products, including circuit breakers, are still in use today.

Westinghouse produced many varieties of circuit breakers. They are known for their reliability and ingenuity. Here is a guide featuring some popular Westinghouse breakers.

Molded Case Circuit breakers

Molded Case circuit breakers are common circuit breakers found in many domestic, commercial and industrial applications. They can handle currents up to 2500 Amps.

Traditional molded case circuit breakers are designed with an electrochemical trip unit that protects against excess current. This is done by combining two devices, one that detects changes in temperature, with the other that detects changes in currents. Molded case circuit breakers use one or a combination of different trip units to protect against thermal overloads, short circuits and ground faults.


Westinghouse’s EH1020 molded case circuit breaker can handle up to 20 amps and 277 volts. It is a single pole circuit breaker.

Like all single pole circuit breakers, the EH1020 provides reliable surge protection for circuits. It can be easily reset once it trips, and takes up little room in a circuit breaker panel.


Westinghouse’s HCA2200 is a molded case circuit breaker. It can handle up to 200 amps, 240 volts and is a double pole breaker.

Like all double pole breakers, the HCA2200 snaps onto two poles inside the circuit breaker panel. Each of these is connects to wirings that are protected by one-half of the breaker. If excess current is detected in one of the sides, both halves of the breaker will trip simultaneously to shut down the entire circuit.


The FB2100 molded case circuit breaker can handle up to 100 amps and 600 volts. Like the HCA2200, it is a double pole circuit breaker.


Westinghouse’s MA3600 is another molded case circuit breaker. It can handle up to 600 amps, 600 volts and consists of 3 poles.

Like all triple-pole circuit breakers, it operates in a comparable way as single-pole circuit breakers. However, it connects three different conductors instead of one. This means it is often used in heavy duty motors as it can protect the circuit from surges across one or more conductors.

Insulated Case Circuit Breakers

Insulated case circuit breakers have similar components as molded case circuit breakers, except it has an additional two-step potential energy mechanism. They function like an iron frame low voltage power breaker, except it is a plastic frame.


Westinghouse’s PC31600 is an insulated case circuit breaker. It can handle up to 1600 amps, 600 volts and contains three poles. It has the similar features as molded case triple pole circuit breakers, except it is made with an insulating case.


The CRD320T55W is another insulated case circuit breaker. Like the MA3600, it is a highly reliable and popular triple pole breaker, with enough capacity to handle 2000 amps and 600 volts.

Vacuum Circuit Breakers

Vacuum circuit breakers are ideal for outdoor applications, as they have the highest insulating strength, making it superior in arc quenching properties. This is due to the arc quenching taking place inside a vacuum.

Vacuum circuit breakers have a different design than other conventional circuit breakers. These breakers consist of a fixed contact, a moving contact, and an arc shield inside a vacuum chamber. Stainless steel bellows connect the moveable component to the control mechanism. Glass or ceramic tubes make the outer body since these materials have high insulating properties.


Westinghouse’s 150VCP-W750 is a vacuum breaker can handle up to 1200 amps and features a draw-out mounting. It has a trip volt, close volt and a charge volt of 125VDC.

Like typical vacuum circuit breakers, it has great insulation and can handle extreme outdoor conditions. This makes the circuit breaker suitable for applications in rural areas.