Standards for Recommended Maintenance of Electrical Systems
Maintenance of electrical equipment is a topic that is not well known by many. It is understandable, since most people have other responsibilities.
CSA provides standards that recommend regular testing and maintenance of electrical equipment.
Insurance companies refer to CSA and other industry standards when determining risk and
customer premiums.
Electrical Maintenance Plan
Below are a few key points to get started on an Electrical System Maintenance Plan.
Step 1 – Electrical Power System Studies and Drawings
Electrical Power System Studies and Drawings are important for safety and maintenance of
electrical power systems.
Updates to studies and drawings must be included with system changes and updated less than 5 years.
Studies can take months to complete and should be completed prior to the outage to assess hazards, equipment ratings and protection settings prior to maintenance.
These studies will confirm drawings to be used for isolation and locking equipment, listing equipment for maintenance and determine settings necessary for the maintenance and testing.
The customer can use the drawings and equipment listings in the study to prepare complete inventory of electrical equipment and components. A maintenance plan with tasks and schedule must be assigned to every item.
Step 2 – Plan and Schedule
Realize that Electrical System Maintenance takes months of preparation.
Prepare, plan and schedule far in advance before problems start. Many electrical components require annual testing and maintenance and require the equipment to be de-energized and locked off for testing.
Consider the best time of year to plan for your next electrical outage. Remember, electric heat is off when the electricity is off. Discuss with all departments how an electrical outage means ZERO ‘0’ electricity, no lights, no power tools, etc. unless powered by a portable generator.
Contact your electrical maintenance company to lock dates in their schedule and ensure resources and spare components are available. Rebuild spare breakers and ensure that they are ready to be exchanged with breakers in service that are due for maintenance.
Step 3 – Condition Monitoring
Infrared Analysis/Thermal Imaging must be performed while the electrical system is energized and operating at maximum electrical load to detect anomalies. In cold climates, this is often in the winter months.
Schedule the Infrared Analysis/Thermal Imaging in advance of the electrical maintenance outage so that problems detected by Thermal Imaging can be repaired during the outage. Transformer Oil and Gas Analysis is another form of condition monitoring used on transformers. Many other electrical tests and measurements are possible on electrical equipment, however, many require electrical outages.
Step 4 – Electrical Equipment Maintenance and Testing
Prepare for the electrical maintenance and testing to be performed during the outage. Prioritize and schedule. During the outage, test and maintain all electrical equipment as per the maintenance plan created in steps above. Exchange rebuilt breakers with others due for maintenance. Document all tests and update all records to prepare for the next sequence.
There are many good books on the subject of maintenance and reliability.
Reliability Centered Maintenance by John Moubray
Uptime by John Dixon Campbell
This is a brief reminder that the maintenance planning process needs planning to be successful and it is a continuous cyclical process. Plan, schedule, execute, update/improve, repeat.
Maintenance Tasks and Frequencies
Below are links to documents that include maintenance tasks and frequencies based on CSA.
Electrical Power System Studies and Drawings
Infrared Analysis of Electrical Equipment
Electrical Equipment Maintenance and Testing
M1 - Switchgear Bus and OH Lines
M2 - Transformers
M3 - Cable
M4.1 - Circuit Breakers
M4.2 - Disconnect and Circuit Switchers
M6 and M7 - Protection, Control, Metering Devices and Instrument Transformers
M8 - Ground Grid Systems
M10 - Motor Control Centers
M12.2 - DC Battery Charging Systems
M13 - Power Factor Capacitors and Reactors