Why Perform Maintenance on my Standby Generator Before a Power Outage or Other Unforseen Problem Arises
The average life expectancy of a well-maintained service vehicle is approximately 5,000 hours (assuming 300,000 miles at 60 mph), a typical standby generator set can last from 10,000 to 30,000 hours. On the other hand, a standby generator might operate as little as 26 hours a year (based on only 30 minutes of weekly exercise and no outages) or as much as several hundred hours a year, depending upon the number and duration of power outages.
In either case, a standby generator set could conceivably last 20 to 30 years. One way to ensure a long, reliable operating life is to implement a preventive maintenance (PM) program.
Preventive maintenance and service are typically done on a schedule based upon engine hours and/or time periods. The maintenance cycle can—and should—be adapted to meet specific application needs. The more hours per year a unit operates, the more frequently it will require service. Environment also plays a role: The more severe the environment (dusty, extremely hot or cold, highly humid, etc.), the more frequent the need for service may be.
Most OEM-recommended maintenance schedules for generators—whether a unit is powered by diesel or natural gas fuels—are roughly the same. The typical maintenance cycle includes a general inspection followed by scheduled inspection and service of the following critical systems.
- Fuel system (diesel fuel requires more maintenance)
- Coolant system
- Lubrication system
- Air system (combustion and cooling air)
- Starting system (batteries and charger)
- Alternator (a frequently overlooked item)
- Transfer switch (another often-overlooked item)
At a minimum, a good visual inspection should be done on a monthly basis, as well as after any extended generator run times. Maintain general cleanliness of the generator and its surroundings. In an enclosed unit, make sure there are no rodents trying to take up residence.
The above items are by no means a complete list. Other PM aspects worth considering include the conducting of weekly exercise periods under load to test the entire system for proper operation and make the generator work at operating temperature. A monthly load test of at least 30% of rated load is required in some applications, using the building load, a load bank or a combination of the two.
OEMs provide detailed standby generator maintenance guidelines that should be followed to provide the longest most reliable service life possible for their respective equipment. General guidelines for specific applications also can be found in several recognized standards. One such standard is the NFPA 110, Standard for Emergency and Standby Power Systems (2018 Edition). It is an excellent resource on general-maintenance requirements and detailed information on some specific maintenance items. This standard also contains a suggested maintenance schedule which, if followed, will meet minimum maintenance requirements for Level 1 and Level 2 emergency standby power systems. Remember: Establishing and following a thorough maintenance and service plan will provide you with a reliable power supply for many years.