TM 9-6115-729-24
0003
GENERATOR SET CONTROL (GSC) - Continued
generator set voltages, currents, and calculated power levels, real and reactive. The generator output voltage,
current, and load bus voltage are monitored and can be displayed on the EMCP displays as desired. LSM A4
monitors the load that the generator powers and allows fine tuning of that load sharing via a speed setting
potentiometer. The LSM sends a speed correction signal to the GSC in order to fine tune the speed based on the
load sharing of the generator. This is utilized primarily when the generator set is in parallel with another
generator. Most engine sensors are connected to the engine control unit and their status transmitted to the GSC
via the CAT Data Link. One engine speed sensor and a low fuel level sensor are directly connected to the GSC.
The engine speed sensor provides positive feedback to the GSC that the engine is operating at the desired
speed. The low fuel sensor initiates a controlled shutdown before the engine runs out of fuel. The ENGINE
CONTROL switch determines whether the engine is to start, stop, or run. The SYNC MODE switch (called
System Mode Switch (SMS) in electrical descriptions) determines the mode of operation with regards to the
paralleling capability. The PUSH TO STOP EMERGENCY STOP pushbutton (also called Emergency
Stop Push Button (ESPB)) immediately stops the engine and should only be used in an emergency. ECM
sends alarm signals to the GSC for any sensors that are directly connected to the ECM.
GSC Outputs
The GSC outputs signals to the display, the ECM, Load Contactor K1, and the EMCP relay module. The GSC
display consists of an upper display, a lower display, and a column of indicators to the left of the upper and lower
displays. The upper display shows the average voltage, frequency, and total current the generator set is putting
out. By pressing the AC METER key on the touch pad, the upper display can display: line-to-line voltage,
generator frequency, and current for each phase; voltage line-to-line for all three phases; line current for all three
phases at once; or voltage line-neutral for all three phases at once. The upper display is also used to display any
fault codes identified by the GSC or by the ECM.
GSC Displays
The GSC lower display is capable of displaying one of the following:
Total Real Power (kW)
Real Power Phase A (kW)
Total reactive power (KVAR)
Real Power Phase B (kW)
Total apparent power (kVA)
Real Power Phase C (kW)
Percentage of rated power (%kW)
Power Factor Phase A
Power factor (average)
Power Factor Phase B
Total energy output (kW/h)
Power Factor Phase C
Total reactive energy output (kVARHr)
The lower display also has a series of arrows pointing downward to symbols printed below the display. These
arrows appear in order to indicate alarm conditions sensed by the GSC and/or ECM. The lower display also lights
up designations K1, K2, etc to indicate the condition of relays K1 through K8 in the relay module internal to the
GSC (Table 1). When a particular symbol appears, the associated relay is energized. This is strictly status and is
helpful when troubleshooting. An additional feature of the lower display is that of a synchroscope. When
manually synchronizing the generator output to another generator, the phase relationship between the generator
and the voltage on the load bus are shown graphically on the lower display. This allows the two systems to be
brought in sync before bringing the generator on line.
0003-24
