Loadbank testing is the single most valuable exercise you can provide for a standby generator. It is intended to burn out the collected carbon from a diesel engine that can diminish performance, but it also allows the operator to test the safety system, cooling system, exhaust system, voltage regulation system, and excitation system while drying out the generator windings.
But it is not required.
30% load for 30 minutes every month.
The loadbank test is only an option for dieselengines in the event you cannot achieve 30% load.
However, the loadbank test is recommended for all standby generators and is often accepted by jurisdictions when gas systems cannot meet the 30% load requirement.
Look at NFPA 110, 2005 edition, chapter 8.4.2. (3)
The requirements are similar in all editions.
Generators and automatic transfer switches as well as their appurtenant devices employ high voltages that can hurt you. Do not attempt to work with this equipment unless you are qualified. Observe all rules and cautions found in the manufacturer's manuals as well as NFPA 70E, Standard for Electrical Safety in the Workplace.
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