Technical specifications for the APP721
The pump manufacturer supplies a completely assembled control panel for the
operation of one or two submersible pump(s) of HP, V and phases.
The control panel is adapted to Flygt pumps. It includes the APP721
microprocessor controller and fault diagnostic system for the control and the
surveillance of a pumping station. It also includes a piezo-electric probe for the
measurement of the water level in the sump.
2 Major Components
In order to accomplish all the necessary functions for the control of pump(s), the
following components are necessary:
2.1 The control panel
All parts are of the best industrial quality designed for extended, reliable and
maintenance-free operation under extremely cold and warm weather
conditions. Electromechanical components are limited to a strict minimum.
2.1.1 The enclosure is of heavy industrial quality in accordance with EEMAC
___ to provide reliable indoor or outdoor operation. The box is fitted with
a heavy steel inner door which is hinge-mounted, and an exterior door (if
necessary) with a 135° angle opening to allow easy access to the
2.1.2 The control panel is equipped with a main disconnect switch mechanically
interlocked with the inner door to electrically isolate the components of the
control panel when the inner door is opened.
2.1.3 For ratings up to 100A, the main disconnect switch is of the fusible type
with fuses rated at 100,000A short circuit ampacity. For ampacities above
100A, the main disconnect switch is a thermal-magnetic circuit breaker
having a fast response, high interrupting capacity and sealed contact
chambers with clear covers for inspection.
2.1.4 Each pump circuit is fitted with a three-pole thermal-magnetic circuit
breaker or current limiting motor protector with instantaneous magnetic
trip and overload relay. The response time under short circuit conditions
is less than one-quarter of a cycle; the action opens all poles thus
avoiding single phase operation of three-phase pumps.
2.1.5 Isolated rotary handles for each motor protector is mounted on the inner
2.1.6 The circuit breaker and overload relay exhibits stable operation under
changing temperature conditions from 25°C below zero up to 40° above
zero. The circuit breaker has a high interrupting capacity independent of
the thermal setting.
2.1.7 Each pump circuit is fitted with a three-pole fast-acting magnetic
contactor, designed for a minimum of 20 years service under normal
operating conditions of pumping stations. Under overload conditions, the
circuit is designed to clear the fault by opening the motor protector or
circuit breaker and then the contactor.
2.1.8 The control panel is fitted with a MANUAL/OFF/AUTO switch to allow
manual pump operation.
2.1.9 The control panel is equipped with not less than 50 Watt heating element
with a thermostat and a protective shield around the heating element to
prevent accidental injuries.
2.1.10 A 100W, 120V convenience outlet is available for connection of a
convenience lamp (optional). All auxiliary circuits are protected with circuit
2.1.11 The control panel and APP721 operate the pump(s) as per the following
Float 1: Indicating a low level alarm and stopping of pump(s)
Probe: Start/stop/alternate the pump(s)
Float 2: Indication of a high level alarm and starting of pump(s)
2.2 The controller
A state-of-the-art microprocessor-based control with fault diagnostics and
display called APP721 is used to provide failsafe operation of the sewage
pumping station. The APP721 control can fulfill, but is not limited to the
2.2.1 The APP721 controls the starting, stopping and, if necessary, alternation
of the pumps. An adjustable software time delay from zero to 9999
seconds, before the starting of a pump is available to prevent the high
inrush current which would result if both pumps were started at the same
2.2.2 The APP721 registers the running time of each pump running separately
and of two pumps running together. It also registers the number of starts
of each pump.
2.2.3 The APP721 calculates, based on level reading values, the inflow and the
outflow of the station. Furthermore, if calculated pump capacity deviates
too much from nominal capacity, the APP721 activates an alarm.
2.2.4 The APP721 calculates, based on the volumetric method, the pumped
2.2.5 The APP721 allows for the protection of operating parameters using a
2.2.6 The APP721 allows for the selection of the operation of one or two pumps
2.2.7 The APP721 allows for the testing of the LED type lights.
2.2.8 The APP721 measures the total number of hours during which the
overflow float has been activated.
2.2.9 The APP721 allows, following a power failure, for the selection of an
adjustable software time delay from zero to 9999 seconds, during which
no pump can start up.
2.2.10 The APP721 allows for the selection of an adjustable software time delay
from zero to 9999 seconds, during which an alarm has to be present in
order for the alarm signal to be issued. This avoids the signal of false
alarms caused by erroneous measurements, or the transmission of these
alarms to the service personnel.
2.2.11 The APP721 can provide the calculated results on a cumulative or daily
basis. If the "PER DAY” report mode is selected, a reset is effected
shortly after midnight. However, the information is stored in the APP721
memory and is available for the central station.
2.2.12 The APP721 constantly monitors the pump to verify if there is no leakage
or any rising of the motor winding. If a pump overheats, the APP721
stops it before overheating. The APP721 provides the same protection
for leakage. For anyone of these two abnormal situations, the APP721
stops the faulty pump and activates an alarm. For these functions, the
control panel will be equipped with the detection module miniCAS II or
MAS711 from ITT Water & Wastewater.
2.2.13 On inspection, the diagnostic display will identify any fault which has
occurred since the last visit, even if the fault has self-corrected and no
longer exists. An alarm silencing push-button is included to stop the
alarm from unnecessary operation once the station operator has taken
notice of the fault.
2.2.14 The APP721 detects and signals the following alarms: overflow, power
failure, high level, low level, and for each pump, motor overload, leakage,
high temperature and capacity error. The operator can acknowledge
these alarms using the alarm register channel.
2.2.15 The APP721 is able to store the last 1000 alarms in a FIFO (First in, First
out) file, with the date and the hour of occurrence. The recording of the
alarms are made in chronological order.
2.2.16 The APP721 has a screen display, easy to use, for reading and
modification of the operating parameters and also for retrieving alarms.
Therefore the modification of the operating parameters is simple and does
not require a programming specialist.
2.2.17 The APP721 is equipped with a KPSI piezo-electric or a LSU-100
ultrasonic level sensor to monitor the well level. From the reading, the
APP721 starts/stops or alternates the operation of the pumps. The
APP721 allows stopping of the pumps at different levels. Fixed values are
attributed to the calibration of the probe and are stored by the APP721.
2.2.18 Using a modem, the APP721 can establish an interactive communication
with an AquaView central system. By doing so, the APP721 will accept
remote commands such as modification of the starting or stopping
parameters. The APP721 will also allow remote transmission of alarms
and data acquisition.
2.2.19 The APP721 allows for the selection of the type of communication: dialed
line, fixed line or radio. In case of dialed line, the APP721 allows for the
selection of the number of ring signals before it will respond.
2.2.20 The APP721 stores the pump operating parameters, (pumps' running
time, number of starts-ups), the inflow, the flows and volumes calculated
for the last 24 hours. This data is automatically transmitted to the central
system, every 24 hours.
2.2.21 The APP721 is fitted with a motherboard which contains the
microprocessor. A real time clock safeguarded by a battery is present to
keep the registration of the alarms and the commands of the pump(s)
functioning at their given time.
2.2.22 The APP721 is protected against signal interference that could occur in
the pumping stations. In order to reduce the sensibility of these signal
interference’s, all inputs and outputs are galvanically-isolated from
2.2.23 The APP721 is equipped with an UPS allowing for continuous reading of
the well level and for data transmission to a remote station, in case of a
power failure. This prevents abnormal situation such as overflow and
flooding. The UPS has an autonomy of approximately 2 hours.
2.2.24 The APP721 has memory allowing recording of set points and operating
values. The information is protected by a nickel-cadmium battery, even in
case of power failure.
2.2.25 The APP721 is equipped with LED indicating the operational functions,
the communication interactions and the alarms state.
2.2.26 The APP721 is equipped with 68 terminals which are used for alarms,
power supply, pump starting, piezo-electric probe connection, digital and
analogue (4 to 20 mA) input signals, etc.
2.2.27 The APP721 is equipped with:
16 digital inputs for alarms (normally open contacts).
4 analogue inputs 1 for level reading probe
8 digital outputs: 2 for pump
1 for alarm relay
2.2.28 The APP721 has a programming memory of 16 MB flash drive and a data
memory of 16 MB. It is supplied with a 24 Vdc, has a power consumption
of 48 VA and an operating temperature range from -20 to 50C.
2.3 Piezo-electric Level Sensor
2.3.1 The piezo-electric level sensor is specifically designed for measuring the
water level in a sump. It is powered by 24 Vdc. The level sensor
measures the pressure of the water in the sump, and gives an analogue
signal to the APP721.
2.3.2 The sensor shall be delivered with 15 meters of cable.
2.4.1 The control panel shall be ready to communicate with the AquaView
central system located at the city treatment facility.
2.4.2 The APP721 shall be delivered with a modem and configured to transmit
operating and running parameters to the central system via a dialed up
2.4.3 Necessary filters shall protect the modem.
2.5.1 The panel shall be equipped with a monitoring relay for leakage detection
and stator high temperature model miniCAS II or MAS711 as fabricated
by ITT Water & Wastewater. In case of a malfunction, the monitoring
relay should stop the pumps. On a high temperature detection a pump
shall not be made available until a manual reset has been performed.
2.5.2 The panel will receive high and low level indication from two ENM-10
floats. The floats shall be mercury free.
2.5.3 The control panel shall be equipped with an UPS to provide approximately
two (2) hours of back-up.
2.5.4 The control panel shall be supplied with the following equipment mounted
on the inner door:
Two (2) time totalizers; one for each pump.
An ammeter per pump with phase selector.
A voltmeter with phase selector.
2.5.5 The control panel shall be supplied with a protective relay against phase
failure and phase reversal.
2.5.6 An alarm silencing push button shall be present to stop the alarm from
unnecessary operation once the station operator has taken notice of the