What Is an Electrical Equipment & Maintenance Checklist?
An electrical equipment & maintenance checklist is a document that contains a list of all the necessary preventive maintenance procedures to ensure that all electrical equipment is in good condition.
This list is usually used for commercial and industrial establishments because they consume a lot of power. And that is why these sectors are only provided with high voltage feeder lines directly from the grid. From there, these sectors provide their own electrical equipment to transform and distribute the electric power to where it’s needed.
Based on years of practice, electrical preventive maintenance (EPM) has been proven to be a great way of identifying and resolving upcoming issues in the electrical system. It may seem at first that implementing an effective electrical maintenance schedule is costly. But it brings several benefits that greatly outweigh the initial costs such as prevention of major breakdowns, reduction of operation disruptions, and prolonging the equipment’s service life.
Aside from that, the continued use of an electrical maintenance checklist ensures an establishment’s compliance with government regulations. The specifics of these regulations may vary depending on the location but, at minimum, the government still mandates the need for continuous electrical maintenance and tests.
For this brief guide, we will be using the National Electric Code (NFPA 70) from the National Fire Protection Agency, an international non-profit organization focused on dealing with fire hazards from various sources which include electrical components.
What Major Electrical Components Should be Checked?
Below are nine major components that should be maintained according to the NFPA 70B Annex 1 Maintenance Intervals. Please take note that the mentioned electrical maintenance schedule below is not set in stone, rather they serve as informational guides when scheduling. Schedules can be adjusted accordingly to other factors such as government mandates or case studies.
1. Substations
Substations are facilities where the high voltage feeder line from the grid is received. It is then distributed to various components such as transformers and switchgear assemblies. To accommodate the incoming high voltage, substations use ground equipment and air-disconnecting switches.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Insulators – visual inspection, infrared scanning, and corona detection
- Conductors – visual inspection and connector tightness test
- Grounding Equipment – visual inspection, connector tightness test, and ground test
- Air-disconnecting Switches – visual inspection, operation test, and connector tightness test
Aside from these, it is also recommended to include substations in the daily electrical maintenance checklist for housekeeping.
2. Switchgear Assemblies
Switchgear assemblies are centralized assemblies of various electrical components such as circuit breakers, switches, protection devices, and fuses to effectively distribute a transformed electrical current. Depending on the amount of voltage they are distributing, these assemblies can be called high-voltage, medium-voltage, or low-voltage.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Ventilation – visual inspection
- Enclosures – security check and operational check
- Insulation – visual inspection, cleaning, and electrical tests
- Space Heater – operational check
3. Transformers
Transformers are electrical components that change the voltage of the electrical current without changing its frequency. These components can be located on the substation and are connected to the switchgear assemblies.
Below are the maintenance procedures (some may not apply to dry-type transformers) based on the electrical equipment & maintenance checklist:
- Reading of voltage, current, and temperature
- Pressure reading
- Turns-ratio test
- Insulation testing
- Dissolved gas analysis
- Fault gas analysis
- Liquid tests and analysis
4. Circuit Breakers
As the name implies, circuit breakers are electrical components that are designed to open and close electrical circuits. They have varying capacities from high voltages to low voltages. And have various mechanisms that it used to operate such as electrical, mechanical, and automatic means. Below are the maintenance procedures based on the electrical equipment & maintenance checklist.
For air circuit breakers:
- Insulators – visual inspection and electrical tests
- Contacts – visual inspection, checking of tightness, and operational tests
- Arc Interrupters – visual inspection, air-puffer test, and electrical tests
- Operating mechanism – visual inspection and operational tests
For vacuum circuit breakers:
- Visual inspection
- Checking of contacts
- Vacuum integrity test
- Electrical tests
For oil circuit breakers:
- Bushings – visual inspection and cleaning
- Oil – dielectric breakdown test
- Contacts – visual inspection and resistance check
Aside from the mentioned maintenance procedures, it is also recommended to include circuit breakers in the semi-annual or annual electrical maintenance checklist for IR scanning.
5. Capacitor Banks
As its name implies, capacitor banks are groups of capacitors connected together to achieve the desired power rating. These components are designed to increase the transmission efficiency of electricity and serve as a buffer for any lagging currents due to high power demand in the system.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Visual inspection
- Fuse check
Capacitor banks can also be included in the annual electrical maintenance checklist for IR scanning.
6. Motor Control Center
A motor control center (MCC) is very similar to a switchgear assembly, but the difference lies in its purpose which is to start and control a group of electric motors. Motor control centers are usually found in establishments that use a lot of pumps and fans. One good example is a shopping mall that has a chilled water plant for air-conditioning.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Busbars and Wiring – visual inspection, checking of connections, and electrical tests
- Contactors – visual inspection and cleaning
- Disconnects – visual inspection, cleaning, and operational check
- Relays – operational check, checking of connections, and calibration
- Interlocks – visual inspection
- Enclosures – visual inspection and cleaning
7. Rotating Equipment (Coupled to an Electric Motor)
This pertains to any equipment that uses an electric motor as its driver. Examples of these are pumps, fans, blowers, and compressors. And as previously mentioned, these are connected to the motor control centers.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Body – vibration analysis
- Stator and Rotor Windings – mechanical inspection and electrical testing
- Commutators and Collector Rings – mechanical inspection
- Bearings – inspection, draining, flushing, and lubrication
8. Fuses
Fuses are electrical components that serve as overcurrent protection to the system. It does so by being designed as having thin links or filament strips that melt and open the circuit if an overload happens.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Fuse – visual inspection and checking of seals and connections
- Terminals and Clips – inspection of contact, checking of contact pressure, and cleaning
- Insulators – visual inspection and cleaning
9. Wiring Devices
Cables and wires serve as a medium for the flow of electricity. And during preventive maintenance, it is inspected to check the quality of its installation and organization. This is important because it affects how easy it is to trace and troubleshoot if there are electrical issues.
Below are the maintenance procedures based on the electrical equipment & maintenance checklist:
- Attachment Plugs and Bodies – visual inspection
Receptacles – visual inspection and operation check
Switches – visual inspection and operation check
What Are the Benefits of a Digital Checklist?
In the age of technology, there’s no reason to do regular equipment maintenance, repairs, and replacements with something as archaic as a pen and paper. Keeping important and official documents on paper is a recipe for disaster. Paper can get torn or ripped, smudged with grease, or lost in the hustle and bustle of an electrician’s busy schedule. With Lumiform’s super intuitive mobile app, maintenance can get done 30%-40% faster, allowing your employees to work on more equipment and make you more money.
Curious to learn more? Here are a few of many more benefits Lumiform has to offer:
- Reports are generated automatically—analyze the results of your electrician’s maintenance work remotely. You can oversee your employees’ work as if you were there in person.
- Create and edit documents on the go—the flexible form builder allows you to conveniently convert all your paper documents into digital checklists within minutes. You can update and edit on the fly via a mobile phone or tablet—online or offline.
- Have access to 12,000 pre-made templates—Worried you don’t know what to include in a checklist? No problem. Lumiform has you covered with our extensive template library. You can even edit already existing checklists to fit the specific needs of your business