We have a 900KW CAT V12 driven genny as part of an automatic emergency switching scheme with two incoming AC lines. One downside is that the automatic mode will start the genset if either line drops, yet inhibit switching to it unless both lines drop. If we know that a line will be down for a while we will often put the switchgear into manual mode and switch to the genset. Our machinists used to run it unloaded every Friday. Now we switch to it and try to load it at least 300 amps per phase and for at least 1/2 hour. I warn that we have no right to expect more from our generator in an emergency than we observe it deliver under normal testing.
This better testing comes with its share of problems. Some of the high efficiency lamps will not maintain through the transfer and take up to 5 minutes to restrike. Failure to time our manual switching correctly might leave us in near total darkness. Folks have to be warned to close their programs and we have to allow them plenty of time before we act. It was a whole lot easier when we just flipped the control switch from "AUTO" to "ON".
Joe
