CAT EMCP 4 - ENGINE SPEED CONTROL; GENERATOR VOLTAGE CONTROL

Application and Installation Guide EMCP 4 SCADA Data Links
©2013 Caterpillar
All rights reserved. Page 21
NOTE: Either this SCADA command OR a digital input Remote Initiate Command will start
the engine – sending False to this register doesn’t prevent the digital input Remote
Initiate from taking effect, and vice versa.
 Emergency Stop Command (1056) – will cause the engine to immediately stop without cooling
down.
NOTE: Either this SCADA command OR the Emergency Stop digital input will stop the
engine – sending False to this register doesn’t prevent the digital input from taking
effect, and vice versa.
 Fuel Pump Primer Status (2087)
 Manual Fuel Priming Duration Remaining (2091) – time remaining in manual fuel priming, in
seconds; only valid while engine is in fuel priming
ENGINE SPEED CONTROL
There are a few registers defined for reading and controlling the target engine speed, as well as
determining whether forced idle is active and whether the engine is actually running in idle. See Chapter 7
for a programming example.
 Requested Engine Speed (1060) – speed being requested by the EMCP 4 to the engine
 Total Speed Bias Percent (1061) - Read the percentage bias being applied to the speed
command output. This is a percent of 200 rpm. This will increment by 0.5% each time the Speed
Adjust left or right arrow is pressed on the EMCP 4 GSC, or any time the Speed Bias Percent
Increment Command (1062) is written. The min/max values for this data are ± 100%.
 Speed Bias Percent Increment Command (1062) - Increments the percentage bias being applied
to the speed command output. This value gets added to the Speed Bias Percent register (the bias
decreases if a negative value is written). The formula is:
T
OTAL SPEED BIAS PERCENT = TOTAL SPEED BIAS PERCENT + SPEED BIAS PERCENT INCREMENT COMMAND
 Forced Idle Command Active (337)
 Low Idle State from ADEM™ (1263)
GENERATOR VOLTAGE CONTROL
There are a few registers defined for reading and controlling the target output voltage of the generator.
See Chapter 7 for a programming example.
 Desired Genset Output Voltage (1057) – the voltage being commanded to the voltage regulator.
The output voltage is limited to being R
ATED ± 40%. However, voltage regulators may have an even
tighter range (e.g. the CDVR is R
ATED ± 15%). When the EMCP 4 is operating in manual voltage
control mode, the formula for calculating the desired output voltage is:
D
ESIRED GENSET OUTPUT VOLTAGE = 1 + 0.4 × (1 + TOTAL_VOLTAGE_BIAS_PERCENT)