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19.10 The external modem does not commence dialing:
A. A null modem cable or adapter is not used and is required from the RS-232 port to the
modem.
B. The modem was not configured properly. Make sure that DTR is always on and that
configuration 0 (zero) is being used and the phone numbers are programmed into the
modem.
20.0 AUTO START OPTION
20.1 If enabled, AUTO START is initiated by either a local contact closure at auto start terminals
or by the receipt of the appropriate serial command string. AUTO START is locked out
whenever an RPM greater than zero is sensed. After an aborted start attempt, the RPM must
return to zero for a minimum of 5 seconds before AUTO START is re-enabled. See the
sequence chart for details.
To automatically start the engine, the AUTO START option must be selected when
programming the system from the PC and the starting procedure sequence defined. The first
step of the AUTO START sequence is an internal reset which clears previous faults and
initializes the PRE-LUBE and DELAY BEFORE CRANKING timers. The Class A safety
shutdown setpoints are continuously monitored and, if faulted, will inhibit the AUTO START
sequence. The Class B and Class C safety shutdown setpoints are automatically disabled
by AUTO START until cranking begins. At the point of cranking, the Class B and Class C
programmed setpoints start their timers and behave as if a RESET command was just
received. This allows the Class B and Class C setpoints to behave in the same manner and
use the same timer values for both AUTO START and MANUAL starting sequences. If a
Class A setpoint should fault during an AUTO START sequence, the system will terminate
the sequence and display the appropriate fault message. Initially, the auto start sequence
energizes the power supply OUTPUT #4, the PRE-LUBE output. This allows for the activation
of an electrically controlled pre-lube pump for a programmed time period 0 to 999 seconds
prior to and/or during cranking. The use of an appropriate warning device which can be used
to alert any personnel near the engine of the forthcoming start attempt is strongly
recommended. This warning device (flashing lights or horn) can be activated by the PRE-
LUBE output directly or thru the use of auxiliary relay contacts. After a user programmed time
delay, adjustable from 0 to 999 seconds when programming the unit ; the engine cranking will
begin. At this time, the Class B and Class C timers will be initialized. The CRANKING motor
is controlled via power supply OUTPUT #3, which would typically be used to control a solenoid
valve or power relay connected to the starting device. After cranking begins, the DE-2500
system implements the engine purge cycle. The engine purge cycle consists of a 5 second roll
without fuel or ignition, followed by a second 5 second delay with ignition and no fuel while
still cranking. After a total purge time of ten seconds, both ignition and fuel have been enabled
via outputs #1 and #2 of the power supply module and the engine should begin running. As
the engine speed increases, a user programmable CRANK DISCONNECT speed switch
function will automatically disable the starter at the selected RPM by de-energizing OUTPUT
#3. If the crank disconnect RPM is not reached within a user programmed time period after
the cranking output is energized (15 to 99 seconds), an OVERCRANK FAULT will be
generated. The OVERCRANK FAULT will turn off the fuel and ignition and disable the starter
until a new AUTO START command is received. After the engine has started and the
cranking device is turned off, the 4-20 ma. RPM control output to the governor will ramp to
the IDLE speed value. The RPM control output will stay at the IDLE value until a user
programmed delay set by the WARM-UP TIMER is completed. After the WARM-UP period,
the RPM CONTROL OUTPUT will ramp to MINIMUM LOAD RPM current. After the governor
responds and the MINIMUM LOAD RPM is reached, automatic control of the compressor
loading by the DE-2500 will begin.
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