Briggs & Stratton 040298, Руководство по обслуживанию и устранению неисправностей

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AUTOMATIC VOLTAGE REGULATOR (AVR)
Accessing the Automatic Voltage Regulator
The Automatic Voltage Regulator (AVR) ( A , Figure 5) is
mounted inside the alternator air intake plenum ( B ).
Figure 5
The voltage regulator acts to increase or decrease current
flow to the rotor windings based on the demands of the load
connected to the generator. The increase or decrease in
current flow through the rotor results in a proportional
increase or decrease in the rotor’s magnetic field strength,
which is what induces (AC) current in the power windings of
the stator.
The operating sequence for this type of voltage regulator is
as follows:
• The rotor turns at a pre-determined speed.
• Voltage is induced into the stator windings by
residual magnetism in the rotor.
Figure 6
• Voltage from the 120VAC stator power windings
are available through wires 11, 12, 33, and 44 to
the circuit breaker. Any electrical load connected
to generator will complete the circuit.
• 120VAC and frequency signals are delivered from
the stator winding via wires 11A and 22A, to the
voltage regulator at sensing terminals 11(
A ,
Figure 6) and 22 ( B ). If for any reason sensing or
frequency is lost, the voltage regulator will turn
off, and it will only turn back on when the
generator is shut down and restarted.
• Excitation winding output is delivered through
wires 2 and 6 to the voltage regulator at excitation
terminals 2 (
C ) and 6 ( D ). If the excitation wire
connections are reversed, the voltage regulator
will shut off.
• The voltage regulator converts the (AC) excitation
winding output to (DC) and delivers the (DC)
output to the rotor via the red wire (
+ ) ( E ), brush,
and slip ring. Then it moves throughout the rotor
winding, the (
- ) brush, and slip ring through the
black wire ( F ). The (DC) output from the voltage
regulator to the rotor is based on the voltage and
frequency signals received from sensing wires
11A and 22A.
Not
for
Reproduction