Low- to Medium-Voltage Circuit Breaker Maintenance and Testing

From: $1,760.00

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About this course…

Circuit breakers are the most critical components of a power system and the facility owner or manager must make sure they are operating properly to maintain both reliability and safety.  Understanding how they work, how they should be operated, how they are tested and how to interpret those test results are necessary even if the repairs and overhauls are performed by a contractor.  This course will provide those details along with basic inspection and repair procedures.

Who should attend…

Technicians, electricians, first line supervisors, and others responsible for full range maintenance, testing and repair of all types of low- and medium-voltage circuit breakers. Intended for those whose intent is to provide service and support of their circuit breakers at a level that would normally be performed by a commercial repair facility, as well as those who may need a deeper understanding of circuit breakers in order to make repairs as needed until a spare breaker can be installed.

You’ll learn…
  • Construction and operation of a variety of molded-case, insulated case and low-voltage power (draw-out) circuit breakers
  • Construction and operation of common medium-voltage metal-clad switchgear and draw-out circuit breakers rated from 2.3 kV through 38 kV
  • Correctly identify circuit breaker ratings and limitations and interpret time-current curves
  • Identify the primary causes of failure and how to correct them
  • Disassemble a low-voltage and medium-voltage circuit breaker, and perform required inspection, maintenance and adjustments; then reassemble
  • How to properly perform and evaluate tests including contact resistance, insulation resistance, AC and DC overpotential, timing, vacuum bottle integrity, primary and secondary injection
  • Maintenance requirements and procedures in accordance with NETA, ANSI, NEMA and NFPA standards
  • Cubicle maintenance and testing, racking mechanisms and control devices
  • Interaction between circuit breakers and cubicles, and protective devices and control schemes
  • Safety aspects of circuit breaker racking, handling and operation
  • Hands-on (~50%) training program augmented with round-table discussions



Students should have basic electrical training, some field experience and basic knowledge of switchgear is highly recommended.

The Details…

Course Length 4.5 days (36 contact hours)

Each open-enrollment student will receive a course text and a copy of the current ANSI/NETA MTS (copy of NFPA 70E available at an additional cost).

Additional information




11/16/15, 02/15/16, 05/02/16, 08/15/16, 11/14/16

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