Table of Contents
Advertisement
CONTROL PANEL INTERIOR
The only equipments discussed in this section will be
those which the operator may have reason to adjust or
inspect for service.
Terminal Board (TB) 2 1 : Connection of wire W12 to
terminals H3, H4, H5, and H6 is made at this point, to
change
reference
voltage
when
reconnecting
generator for different voltages. Refer to Figure 1.
Voltage Regulator, Begin Spec G: Solid state unit,
consisting of printed circuit board VR21; an SCR
bridge CR21, with a commutating reactor L21 are
located in the control panel as part of the voltage
regulator system. AC output from generator is con-
trolled at predetermined level regardless of load;
regulation is plus or minus 2% from no load to full
load, at 0.8 P.F.
Voltage Regulator, Prior to Spec G: Solid state unit
consisting of printed circuit board VR21.
An exciter-regulator assembly designated VR22 containing an SCR
bridge circuit and commutating reactor is mounted on the
generator end bell (see Figure 4) and works in conjunction with
VR21.
Engine Monitor: Printed circuit plug-in modules
provide the following functions:
1. A 75 second cranking period.
2. Approximately a 12.5-second time delay for oil
pressure buildup.
3. An external alarm contact to light afault lamp and
shut down the set for alarm conditions such as:
a. Overcrank (failed to start after cranking 75
seconds).
b. Overspeed (enginespeed reaches2100 r/min).
c. Low oil pressure 14 psi (96.5 kPa).
d. High engine temperature 215° F (102°C).
On standard control panels, all four alarms are wired into one
common fault lamp; on units with five fault lamps, four have
shutdown alarms, the fifth (low engine temperature) lights a fault
lamp only. Refer to Table 2.
Standard Cranking Module: Limits engine cranking
time to 75 seconds. If engine fails to start after 75
seconds the engine monitor lights a fault lamp and
opens the cranking circuit.
EXCI TER-REGULATOR
CHASSIS ASSEMBLY
(PRIOR TO
1
SPEC Q)
N D B E L L
OVERSPEED SWITCH
ROTATING EXCITER
WITH RECTIFIERS
FIGURE 4.
GENERATOR (GRILLE REMOVED)
OPTIONAL MODULES
Cycle Cranker Plug-in module replaces standard
cranking circuit. Automatically provides a 15-second
crank time and a 10-second rest time for three ON and
two OFF cycles in 65 seconds. If engine fails to start,
after 75 seconds the engine monitor lights a fault lamp
and opens the cranking circuit. The ON and OFF
cycle times are nominal and can be adjusted at
potentiometers on the cranker module board.
Pre-Alarm: Gives advance warning for low oil
pressure or high engine temperature. Requires two
sensors each for engine temperature and oil pressure.
Hide quick links:
Advertisement
Table of Contents
