10
Operation
DPCT IOM InsTruCTIOn OPeraTIOn Manual
MN124018EN January 2023 www.eaton.com
AUTO START” input the controller will start and run for the
duration of the MRT.
The purpose of the MRT is to ensure that the engine is not
subjected to frequent starts in response to the pressure.
Refer to Appendix D for programming of the MRT.
4.3.4 Sequential start timer (SST)
The Sequential Start Timer is standard in all DPCT fire
pump controllers.
The controller for each unit of multiple pump units shall
incorporate a sequential timing device to prevent any one
driver from starting simultaneously with any other driver.
Each pump supplying suction pressure to another pump
shall be arranged to start within 10 seconds before the
pump it supplies. The controllers for pumps arranged in
series shall be interlocked to ensure the correct pump
starting sequence. If water requirements call for more
than one pumping unit to operate, the units shall start at
intervals of 5 to 10 seconds. Failure of a leading driver to
start shall not prevent subsequent drivers from starting.
The sequential start timer (SST) delays the starting of a fire
pump in response to the pressure sensor or “REMOTE
AUTO START” input. It does not delay a “REMOTE
MANUAL START”.
With an SST in each controller, any pump may be selected
as the lead pump by appropriate setting of the timers. If the
lead pump restores the pressure in less than the time delays
applied to the lag pumps, then the lag pumps will not start.
In addition, the provision of a sequential start timer, set to a
few seconds delay, will prevent the lead pump controller from
responding to momentary hydraulic transient pressure loss
which would otherwise start the fire pump unnecessarily.
The SST can be programmed from 0 - 300 seconds.
Typically, each pump should be delayed by 10 seconds from
the pump ahead of it.
4.3.5 Control Inputs
The DPCT has ten (10) programmable inputs.
CAUTION
SEVERE DAMAGE COULD BE CAUSED TO THE
MICROPROCESSOR BOARDS IF A VOLTAGE IS APPLIED
TO THESE INPUTS. THEY ARE INTERNALLY POWERED.
4.3.5.1 Control input descriptions
NOTICE
The below definitions of the control input functionality
assume that “Fail Safe” programming is disabled for each
control input condition.
The Control Input state definitions are as follows.
Connected -
When the input is shorted by an external
contact or connection.
Disconnected -
When the input is NOT shorted by an
external contact or connection.
The Control Input operations are defined as follows.
ote:
N
Terminal 49 is common to all the inputs
outlined below.
4.3.5.1.1 Remote manual start
When this input is in the “Connected” state, the controller
will initiate the crank cycle. Remote Manual Start will
ignore the sequential start timer (SST) and the minimum
run timer (MRT) and will require a manual stop signal to
shut down the pump. This input is typically wired to a
remote pushbutton to allow for remote manual starting of
the controller.
4.3.5.1.2 Remote manual stop
When this input is in the “Connected” state it will shut
down the engine by energizing the Fuel Stop relay.
4.3.5.1.3 Remote manual start/stop
When this input is in the “Connected” state, the controller
will initiate the the crank cycle. When this input is
“Disconnected” it will energize the Fuel Stop relay until the
engine has shut down then it will resume normal operation.
4.3.5.1.4 Remote auto start
When this input is in the “Connected” state and the SST,
if enabled, has elapsed the DPCT controller will initiate the
crank cycle. When this input is “Disconnected” the DPCT
Controller will energize the FUEL STOP relay after the MRT
has elapsed
ote:
N
When the controller is programmed for foam
operation, the remote auto start input be a
normally closed input that will open to initiate a
start.
4.3.5.1.5 Deluge valve start
When this input is in the “Disconnected” state and the
SST, if enabled, has elapsed the DPCT controller will initiate
crank cycle. When this input is “Disconnected” the DPCT
will energize the FUEL RELAY once the MRT has elapsed.
If programmed to automatically shut down the pump,
when the input is in a “Connected” state and the MRT has
elapsed, the controller will shut down the pump. This input
is typically wired to remote water control equipment that
starts the controller before the pressure transducer does.
4.3.5.1.6 Low suction
When this input is in the “Connected” state, the DPCT
controller will signal a visual indication in the notification
area for Low Suction. If the controller is programmed
for Low Suction Shutdown it will initiate the shutdown
sequence. Refer to Section 5 to program Low
Suction Shutdown.
