Preventive Maintenance Checklist: Circuit Breaker (Magnum DS)

• Site conducted

  Select

• Conducted on

  Date

• Prepared by

• Location

• Asset Type

  Yes

  No

  N/A

• Frequency

  Yes

  No

  N/A

• Work Order Number

  Yes

  No

  N/A

(T)ools, (S)afety Equipment and (M)aterials

• Electrician's tool set

  Yes

  No

  N/A

• Lubricants

  Yes

  No

  N/A

• Cleaning tools and materials

  Yes

  No

  N/A

• Vacuum cleaner

  Yes

  No

  N/A

• Micro-Ohmmeter

  Yes

  No

  N/A

• Magnum DS test equipment

  Yes

  No

  N/A

• Replacement battery

  Yes

  No

  N/A

Safety Guidelines

• This maintenance task should be performed only by personnel qualified in maintaining power circuit breakers and switchboard instruments

  Yes

  No

  N/A

• Follow the site safety rules and your supervisor's instructions

  Yes

  No

  N/A

• Schedule the work with the users

  Yes

  No

  N/A

• Report any problems you find

  Yes

  No

  N/A

• Record the results in the maintenance log

  Yes

  No

  N/A

Maintenance Procedures

• 2 YEARS - ACTIVE BREAKERS ONLY

  Yes

  No

  N/A

• Test the breaker open and close function:

  Yes

  No

  N/A

• Charge the spring breaker mechanism

  Yes

  No

  N/A

• Remove the control power fuses so the breaker spring mechanism doesn't recharge

  Yes

  No

  N/A

• Manually perform three open and close operations to verify proper operation of the charge spring mechanism

  Yes

  No

  N/A

• Recharge the spring mechanism

  Yes

  No

  N/A

• Close and open the circuit breaker three times electrically to verify operation of the breaker close and trip features

  Yes

  No

  N/A

• Replace the control power fuses

  Yes

  No

  N/A

• Check the condition of the arc chutes

  Yes

  No

  N/A

• Inspect the condition of the primary contacts. Measure and record contact resistance

  Yes

  No

  N/A

• Check all connections for proper torque

  Yes

  No

  N/A

• Check the condition of the breaker and switchboard connection tabs

  Yes

  No

  N/A

• Thoroughly clean the circuit breaker

  Yes

  No

  N/A

• Test the circuit breaker in the racked-out position prior to returning it to service

  Yes

  No

  N/A

• Test the battery in the Digitrip electronic trip units

  Yes

  No

  N/A

• Rack the breaker back into the switchboard

  Yes

  No

  N/A

• Use the test kit to test the trip unit operation

  Yes

  No

  N/A

• Test the racking and interlock command sequences

  Yes

  No

  N/A

• Open and close the circuit breaker remotely, using the different auxiliary devices

  Yes

  No

  N/A

• Return the circuit breaker to service and perform an operational test of the normal and emergency

  Yes

  No

  N/A

• Return the circuit breaker to service and perform an operational test of the normal and emergency modes

  Yes

  No

  N/A

• Record the number of operations shown on the counter