Generating Power to the World
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PTI-15/20-T4F Operators Manual
low voltage that air
conditioning will have more difficulty in starting, and long
starting lines may overload generator and trip circuit breakers.
For three phase connections, please contact Power Technology’s Tech support
Dept.
EXCITER FIELD COIL VOLTAGE SOURCE
Field coil DC voltage is obtained by rectifying the voltage from the phase to
neutral line of the generator output, or either appropriate terminal to provide the needed
voltage reference.
The rectifier bridge is an internal part of the static regulator. The static regulator senses
a change in the generator output and automatically regulates current flow in the exciter
field coil circuit to increase or decrease the exciter field strength. An adjustable rheostat
sized to be compatible with the regulator is used to provide adjustment of the regulator
sensing circuit.
ROTATING FIELD ASSEMBLY (ROTOR)
The rotating field assembly consists basically of four members: 1) the shaft
assembly, 2) the core assembly, 3) the field coil damper windings, and 4) balance lugs
to provide a high degree of static
and dynamic balance.
CORE ASSEMBLY
The core assembly consists of a quantity of thin steel plates compressed and
fastened together to form a single laminated assembly. The field windings are wound
around this assembly.
FIELD COIL
Field coils of heavily insulated wire are “wet” wound directly onto the poles. Field
coil leads are brought out to the rectifier assembly for connection to the source of
DC excitation voltage.
BALANCE
The rotor assembly is precision balanced to a high degree of static and dynamic
balance. Although the balance will remain dynamically stable at speeds in excess of the
design frequencies, the prime mover should be adequately governed to prevent
excessive over speed. High centrifugal forces created by excessive over speed may
damage the rotor windings and field coils.
