Load Bank Testing

Load Bank Testing And Inspection

Industry trade organisations and manufacturers both agree that a well-planned preventive maintenance programme is vital to the reliable operation of a standby generator. Load bank testing is an essential part of such a programme. Load banks provide a practical means to test the system without interruption to the critical loads.

A load bank is a stationary or mobile piece of equipment that provides operator-adjustable electrical resistance or resistance and reactance to simulate the actual electrical load the generator is intended to power.

Load Bank Testing

Load bank testing simulates the electrical demands of one or more items of electrical equipment, specific processes within the plant, or an entire facility. The load bank test will ensure that both engine and alternator can cope with the load demand.

It is advisable to perform load bank testing on an annual basis, because it can eliminate problems brought on by neglect and underutilisation. Weekly test operation under no-load or light-load conditions does not permit engine fluids to attain proper operating temperature. Cooling system controls will not be properly exercised, preventing coolant from circulating through radiators, and inviting failures stemming from inactivity. Engine safety shutdown systems are not subjected to actual operating conditions and are therefore not fully tested.

Diesel-driven units are subject to a particular problem known as ‘wet stacking’ or ‘slobbering’ that stems from operation under no-load or light-load conditions. Such operation causes fuel deposits to collect on the combustion chamber, injector nozzles, piston rings, turbocharger and exhaust system. The result is diminished engine output capacity. Regular load bank testing burns off accumulated deposits and preserves engine output capability.