- Owner
- Maintenance Manager
- Effective date
- September 15, 2026
- Review cycle
- Every 12 months
1.Purpose
To make sure standby generators start and carry load reliably when needed, by keeping fluids, batteries, fuel and controls maintained and tested on a regular schedule.
2.Scope
Applies to standby and backup generators used for emergency or backup power. Portable generators used for temporary equipment power are covered by a separate procedure.
Definitions
- No-load test
- Starting and running the generator without connecting it to the building or equipment load, to confirm it starts and runs correctly.
- Load bank test
- Running the generator against a controlled test load to confirm it can carry its rated capacity, since standby generators rarely see full load in normal operation.
- Transfer switch
- The device that automatically switches power supply between utility power and the generator during an outage.
- Run hours
- The cumulative hours a generator has operated, tracked to schedule service intervals.
3.Responsibilities
- Maintenance Technician
- Performs visual inspections, fluid checks and routine test runs, and logs results.
- Maintenance Electrician
- Tests the transfer switch, battery charging system and electrical connections.
- Maintenance Manager
- Reviews test results, schedules annual service and load bank testing, and approves corrective repairs.
- Facility Manager
- Coordinates test timing with building operations and is notified of any generator that fails a readiness test.
RACI matrix
| Activity | Maintenance Technician | Maintenance Electrician | Maintenance Manager | Facility Manager |
|---|---|---|---|---|
| Perform the routine visual inspection | R/A | I | I | - |
| Perform the no-load start test | R/A | C | I | I |
| Perform the load bank test | R | R | A | C |
| Test the transfer switch | C | R/A | I | C |
| Schedule annual service | I | I | R/A | C |
R = Responsible, A = Accountable, C = Consulted, I = Informed
4.Materials and PPE
Materials, tools and systems
- →Generator PM schedule and manufacturer service manual
- →Multimeter and battery load tester
- →Fuel quality test kit
- →Load bank test equipment or contracted load bank service
- →Generator run log
- →Spill containment supplies
Personal protective equipment
- →Safety glasses
- →Hearing protection
- →Insulated gloves for electrical checks
- →Fuel-resistant gloves when checking the fuel system
5.Procedure
- 5.1
Review the PM schedule and run hours
Maintenance TechnicianTechnician checks the generator's PM schedule and current run hours in the CMMS to confirm which tasks are due this visit.
- 5.2
Perform the visual inspection
Maintenance TechnicianTechnician inspects the generator enclosure, engine and fuel lines for leaks, corrosion, loose connections or physical damage.
- 5.3
Check engine oil and coolant levels
Maintenance TechnicianTechnician checks engine oil and coolant against the manufacturer's specified levels and tops up or schedules an oil change if due.
- 5.4
Test the battery and charging system
Maintenance ElectricianElectrician load-tests the starting battery, checks terminal connections for corrosion, and confirms the battery charger is maintaining the correct float voltage.
Warning: Treat battery terminals as energized; wear insulated gloves and avoid creating a short across the terminals.
- 5.5
Check the block heater and starting circuits
Maintenance TechnicianTechnician confirms the block heater is warming the engine to the specified temperature and checks starting circuit wiring for damage or loose connections.
- 5.6
Perform the no-load start test
Maintenance TechnicianTechnician starts the generator and runs it unloaded for the specified time, checking oil pressure, coolant temperature and voltage output against normal ranges.
Checkpoint: Generator reaches rated voltage and frequency within the manufacturer's specified start time.
- 5.7
Inspect the fuel system and quality
Maintenance TechnicianTechnician checks the fuel tank level, inspects for water or contamination using the fuel test kit, and confirms fuel filters are within their service interval.
- 5.8
Test the transfer switch
Maintenance ElectricianElectrician simulates a utility power loss to confirm the transfer switch signals the generator to start and switches the load over within the expected time.
Checkpoint: Transfer switch completes the changeover within the manufacturer's specified time during the simulated outage.
- 5.9
Perform the periodic load bank test
Maintenance ManagerTechnician and electrician run the generator against a load bank at the interval specified in the PM schedule to confirm it can carry its rated capacity without wet-stacking or overheating.
- 5.10
Check exhaust and ventilation
Maintenance TechnicianTechnician inspects the exhaust system for leaks or damage and confirms generator room or enclosure ventilation louvers are clear and functioning.
- 5.11
Record run hours and test results
Maintenance TechnicianTechnician logs run hours, test readings, fuel level and any alarms or faults observed in the generator run log and the CMMS.
- 5.12
Address alarms and schedule annual service
Maintenance ManagerMaintenance manager reviews any alarm or out-of-range reading, arranges corrective repair, and schedules the manufacturer-recommended annual service with a qualified technician.
6.Quality checks
- →No-load start tests are completed on the full PM schedule with no missed intervals.
- →Every load bank test result is compared against the generator's rated capacity.
- →Transfer switch changeover time is recorded and compared to the manufacturer's specification.
- →Fuel quality is tested at the scheduled interval and any contamination is addressed before the next outage.
7.Records
- →Generator run log with test results
- →Load bank test reports
- →Transfer switch test results
- →Annual service records
8.KPIs
- →Percentage of scheduled test runs completed
- →Generator failures to start on demand
- →Load bank test pass rate
- →Average transfer switch changeover time
9.Common mistakes
- →Only performing no-load tests and never load bank testing the generator.
- →Letting the battery charger go unchecked until the battery fails to start the engine.
- →Skipping fuel quality checks on generators that run infrequently.
- →Not recording run hours accurately, causing missed service intervals.
- →Assuming a successful no-load test means the generator can carry full building load.
10.Revision history
| Revision | Date | Description | Reviewed by |
|---|---|---|---|
| 1.0 | September 15, 2026 | Initial release | Ilia Pirozhenko |
This is a template. Adapt it to your organization, equipment and local regulations before use.
