If your building has an automatic transfer switch that controls an emergency generator, keeping it well serviced is critical to accessing generator power when you need it. But where do you find the right transfer switch service provider? In some cases, companies have their own technicians that specialize in transfer switch maintenance and testing. But in most cases, a supplier of emergency power equipment that offers transfer switch installation and maintenance is retained. When you hire such a company to maintain your transfer switch, you can expect four types of service from a full service agreement: weekly inspection, monthly testing, annual testing, and annual maintenance.
1. Weekly Inspection
A weekly transfer switch inspection should occur within the context of a weekly emergency power system inspection, which should ensure that: indicator lamps are functioning properly, control switches are in the automatic position, and no signs of malfunction or overheating are present. To identify overheating and other problems in their infancy, infrared scanning, which detects abnormal heat patterns emanating from compromised electrical components, offers top preventative maintenance. Performing infrared scanning on a quarterly basis is ideal.
2. Monthly Testing
Your emergency power system should be tested every month, with your power switch beginning the test by signaling the generator to start, then transferring load to the generator set. With the test complete, the switch should return the load and shut down the generator after a brief period. Monthly testing of your emergency power system assures two things: your transfer switch can detect a power failure and switch over to generator power as planned, and your generator can start as planned and carry load.
Annual Testing
Because loose cables, worn contact assemblies, and power overload can cause transfer switch failure, NFPA 110 and NFPA 70B require transfer switches to be tested annually, preferably using a full power failure test by manipulating a switch's circuitry. If switch failure occurs during a power outage, its normally energized state can make it difficult to restore to working order, with a fix often taking hours. If your building depends on constant electric supply to maintain data or support medical equipment, the loss that occurs from hours of no electricity could be immense.
Annual Maintenance
In addition to requiring the annual testing of transfer switches, NFPA 110 and NFPA 70B also require their annual maintenance. For fully functioning switches, maintenance amounts to simple preventative measures performed with precision and care after the switch is disconnected from utility power and generator connections, particularly: cleaning of the cabinet's interior that houses the switch, cleaning of the switch's surfaces, inspection of contacts for corrosion and heavy wear, and inspection of the switch for cracks, corrosion, heavy wear, or other forms of deterioration.
