What does NFPA 110 require for load bank testing?
NFPA 110 requires emergency and standby generators to be tested under load. Diesel sets that do not reach about 30% of their nameplate rating in normal operation must be exercised with additional load — supplied by a load bank — to prove rated output and prevent wet stacking, typically annually.
How do you load bank test a generator?
Connect a load bank rated to the generator's kW, start the generator, step the load up to rated output, hold at full load until temperatures stabilise and wet stacking is burned off, then log kW, voltage, frequency and temperatures for the record.
What is wet stacking and how does a load bank prevent it?
Wet stacking is the build-up of unburned fuel and carbon in a diesel generator that is chronically under-loaded. Running the set at full load with a load bank raises exhaust temperatures and burns off that build-up, keeping the engine healthy.