Alfalaval EPC-400 User manual

Alfa Laval Marine & Power
EPC-400
Control Unit
P000681A
Product No.
Printed
Book No.
31830-6149-1
31830-6149-2
31830-6149-3
31830-6228-1
31830-6228-2
31830-6228-3
Nov 1998
1818053-02 V3
Component
Description

Alfa Laval reserve the right to make changes at any time without
prior notice.
Any comments regarding possible errors and omissions or
suggestions for improvement of this publication would be
gratefully appreciated.
Copies of this publication can be ordered from your local Alfa
Laval company.
Published by: Alfa Laval Marine & Power AB
S - 147 80 Tumba
Sweden
© Copyright Alfa Laval Marine & Power AB 1998.

1818053-02
Contents
1 Overview 1
2 Function Description 3
2.1 Application 3
2.2 Working Principle 3
2.3 Design 4
2.3.1 Front Panel 4
2.3.2 Label Inside the Front Panel 5
2.3.3 Control Module 5
2.3.4 Power Supply 6
3 Operation 7
3.1 Process Operation 7
3.2 Parameter Setting 7
3.2.1 Overview 8
3.2.2 Setting Procedure 8
4 Maintenance 11
4.1 Preventive Maintenance 11
4.1.1 Lamp Test 11
4.2 Corrective Maintenance 12
4.2.1 Fuses and Related
Functions 12
4.3 Replacement of
Control Module 13
5 Technical Data 15
5.1 Specification 15
5.2 Dimensions 16
5.3 Circuit Diagram 17
6 Installation 19
6.1 Mounting 19
6.2 Cable Routing 20
6.3 Location of Cable Entries 20
6.4 Terminal Protectors 21
7 Spare Parts 23

1818053-02

1818053-02 1
1 Overview
EPC-400 control unit is used within a
separation system for automatic control of the
separation process.
The unit is microprocessor based and
comprises output functions for control of
ancillary equipment and input functions for
monitoring and alarm. The EPC-400 is
programmable to suit different separator
systems and different operation conditions.
The programming can easily be adjusted to
new conditions or new experience.

1 Overview EPC-400
21818053-02

1818053-02 3
2 Function Description
2.1 Application
The EPC-400 control unit is used in ALCAP
separation systems.
2.2 Working Principle
The EPC-400 is used for monitoring and
control of the separation process. It controls
starting, separation, sludge discharge and
stopping sequences.
The process is monitored via input signals
from sensors, etc., and an alarm is given if
preset values are exceeded.
The unit also contains a PI-controller for
temperature control which can operate an Alfa
Laval Heatpac electric heater or a steam
heater or any other heater with control valve
(for steam / hot water /thermal oil).
The control unit can be programmed for
different separator systems and for different
conditions within the system. The
programming is made by setting parameters,
such as type of equipment, temperature limits,
times, etc. Some parameters are set at
installation whilst process parameters are
easily accessible for adjustment during
operation.

2 Function Description EPC-400
41818053-02
2.3 Design
2.3.1 Front Panel
The front panel of the EPC-400 control unit
provides a display and LEDs (light emitting
diodes) for alarm and process information,
and push-buttons for on/off and manual
process control.
Four push-buttons are located to the right on
the panel. The upper three (1–3) are used for
process functions and the lower (4) is used for
alarm reset. The push-buttons are also used for
parameter selection and setting.
On and off functions corresponding to the
push-buttons are indicated on the LEDs (6–8)
above the display. The LEDs under the
display (9–10) are used for alarm indications.
The five digit display (11) shows process
information during operation and alarm codes
at certain alarms. It is also used for parameter
selection and setting.
The left part of the front panel contains two
rows of LEDs. The upper row (12) indicates
alarms. The alarm source is indicated on the
upper schematic diagram (13).
The LEDs in the lower row (14) indicate when
an output from the control unit is active. The
valve or other unit connected to each output is
indicated on the lower schematic diagram
(15).
The schematic diagrams can be replaced in
case of system changes or updates.
The front panel can be swung open like a door
by opening the lock (16) to the left.
G001145A
G001141A
1. Heater on/off push-button
2. Control program on/off push-button
3. Sludge discharge push-button
4. Alarm reset
5. Function symbols
6. LED for heater (green)
7. LED for control program running (green)
8. LED for stop sequence running (yellow)
9. LED for discharge failure (red)
10. LED for common main alarm (red)
11. Display
12. LEDs for alarm inputs (red)
13. Schematic diagram, alarm inputs
14. LEDs for output functions (green)
15. Schematic diagram, outputs
16. Door lock

EPC-400 2 Function Description
1818053-02 5
An on/off switch combined with a fuse is
located behind the front panel. The power is
intended to be permanently on. When work is
to be carried out in the control unit the mains
supply should be externally switched off.
2.3.2 Label Inside the Front Panel
A label on the inner side of the front panel,
serves as a quick reminder for parameter
setting in the EPC. It shows:
•the positions of the mode switch
•the connection between the display and
the push buttons
•the meaning of some parameters (P)
To make use of the label you must be familiar
with parameter setting, see section
“Operation” in this manual, and parameter
values, see the “Parameter List” manual.
2.3.3 Control Module
All electronic components are grouped on two
circuit boards which are mounted in a hinged
aluminium frame, forming an easily
accessible control module (1) inside the
cabinet. The module is fastened by two
screws, making it easy to remove and service.
Electrical output and input connections to the
module is made by cables terminated with
multi-plugs that fit into sockets on the circuit
board.
The front circuit board controls the operating
sequences. It holds the operating push-buttons
(5, 6), mode switch (3) and display segments
(4).
G001161AP000591A
1. Control module
2. Front circuit board
3. Mode switch
4. Display
5. Push buttons (for parameter setting)
6. Push buttons (for parameter selection)
F1–F3
Fuses
F11.Main switch/main fuse
X-. Terminals

2 Function Description EPC-400
61818053-02
It also contains built-in relays, which are used
e.g. for the output signals to ancillary
components, stop signal to the separator motor
starter and control signals to an optional
heater.
The rear circuit board (2b) monitors the water
transducer and coordinates the monitoring
with the operating sequences for the ALCAP
functions.
2.3.4 Power Supply
Inside the cabinet, behind the control module,
there is a mounting plate with terminals (XA),
power line filter (Z1) and a transformer (T1).
P000612A
1. Control module (folded out)
2b. Rear circuit board
F1, F2 fuses
F11 Main switch/main fuse
T1 Transformer
Z1 Power line filter
XA Terminals