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Figure 15 Field Flashing
To restore the small amount of residual magnetism necessary to begin
the voltage build up, connect a 12 or 24-volt battery to the exciter field
coil circuit and flash as follows:
1. Open the output circuit breaker, and stop the engine.
2. Disconnect the exciter field coil wires EF1 at the terminal EF1
and EF2 at the terminal EF2, and connect the battery positive
lead to the field coil lead EF1.
3. Flash the field by touching the battery lead to the field coil circuit
terminal EF2.
4. Disconnect the battery leads.
5. Reconnect the field coil lead EF1 to terminal EF1, and reconnect
the field coil lead EF2 to terminal EF2.
6. Start the generator, and check for voltage build up. Reflash if
the generator output voltage does not build up, or flash with the
generator running, the field coil wires connected to the regulator,
and a 3-amp or larger diode off the positive terminal of the
battery per Figure 15.
Continuous Operation
Operate the generator within the nameplate values. If the generator is
operated below the rated power factor and voltage, decrease the kVA
to prevent overheating of the field and stator windings. Consult the
factory for derating factors if the application requires the unit to be
operated beyond nameplate values.
Rotor overheating may occur when the generator is carrying excessive
unbalanced loads. Negative sequence currents flowing in the field pole
face cause the rotor heating. For a general guide to the allowable phase
unbalance, see Figure 16 (which is based on a 10% equivalent negative
sequence current).
12 or 24 V Battery
Voltage
Regulator
3 A or Larger
Diode
EF1
EF2
Содержание 4P10
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