Load testing of client-owned generator sets ensures that the equipment can safely and reliably take its rated load for a predetermined time without failure.
Webster Group has a fleet of load banks available for hire ranging from 20 kVA to 3000 kVA, some of which are equipped with paralleling abilities, and which can produce tabulated and graphed results for clarity of presentation.
Onsite load testing
Our skilled technicians are available to conduct onsite load testing as part of our standard generator maintenance package, or assist in specific load testing applications, such as power factor correction commissioning and testing.
Both resistive and inductive loads are required for testing AC supplies at non-unity power factors. Since most gensets are rated at 0.8 power factor, testing at full electrical load ratings can only be done with a combined load bank.
Both leading and lagging power factor simulations can be arranged using our equipment.
Why Load Test?
Load bank testing validates the operational performance of a generator. It tests the power output stability and the generator’s various operating parameters under full load nameplate-rated conditions, and is usually carried out during regular preventative maintenance. Load bank testing is particularly important for emergency and back-up power supply generators to ensure they will work when required, typically in the event of a mains failure when systems-critical power is vital.
Operators need to know a generator will actually run fully loaded when required with a safe margin above this as per the original design. Load bank testing will indicate the engine’s ability to provide this required power; stable frequency; oil and fuel pressure; the alternator’s capability to provide the required balanced and stable voltage; reliability and accuracy of control systems under varying conditions of load; performance of the whole system.
It will also help remove deposits from pistons, engine castings and exhausts, and identify potential weaknesses.
Critical engine systems are continuously monitored throughout the load test to ensure they are within safe operating ranges, and a record made of results. Any work that needs to be done is then tabulated.
Alternator insulation resistance testing also ensures that the alternator winding insulation is within minimum specifications. Low readings indicate that moisture absorption or insulation varnish deterioration has occurred, which could lead to alternator failure. With advanced warning, simple remedial actions can be taken to avoid expensive failures from occurring.