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EC2-742_65110_EN_R03.doc
Replacement for Rev.:02
1 / 4
16.09.2009
EC2-742 Condenser Controller
Operating Instructions
GB
Note: This document contains short form instructions for experienced users.
Use last column in List of Parameters to document your individual settings.
More detailed information can be found in the User Manual.
The
EC2-742
controller is for use in condensers with speed controlled fan(s).
Based on the input signal from a pressure transmitter (1) an analogue 0…10 V
output signal is provided, which can be used for fan speed power modules (3) as
the FSP-series from EMERSON, see following drawing:
The PT pressure transmitter (1) senses condensing pressure and feeds the signal
into a proportional control loop with proportional band (P1) around setpoint (P0).
This control loop generates a 0…10V output signal to modulate the speed of
condenser fan motor(s) (3) by using the FSP Fan Speed Power Module (10).
Digital outputs allow to switch a stage solenoid (5) and a sprinkler valve (4).
Sprinkler
Solenoid
2-stage
Solenoid
Fan
Speed
Output
Condensing
Pressure
P8 is the setpoint and P9 the differential to activate a sprinkler. P3 is the setpoint
and P2 the differential to activate the solenoid valve for two stage condenser
operation.
A NTC temperature sensor (2) may be attached for ambient air temperature
measurement. This can be used for setpoint floating. Depending on ambient
temperature, the condensing pressure setpoint may be lowered in a controlled way
resulting in a reduction of energy consumption of the overall system.
A fast recovery procedure can be used to immediately switch off fan(s) when the
condensing pressure falls below a set limit. Similarly an emergency routine can be
activated automatically if the condensing pressure exceeds a definable limit.
!
Safety instructions:
•
Read installation instructions thoroughly. Failure to comply can result in
device failure, system damage or personal injury.
•
The product is intended for use by persons having the appropriate
knowledge and skills.
•
Ensure electrical ratings per technical data are not exceeded.
•
Disconnect all voltages from system before installation.
•
Keep temperatures within nominal limits.
•
Comply with local electrical regulations when wiring
Technical data:
Power supply
24VAC ±10%; 50/60 Hz; Class II
Power consumption
4VA max.
Communication TCP/IP
Ethernet
10MBit/s
Terminals
Removable screw terminals
wire size 0.14 … 1.5 mm
2
Temperature
storage
operating
-20 … +65°C
0 … +60°C
Pressure sensor input
24VDC, 4 … 20mA
Temperature sensor input NTC (10K at 25°C )
Condenser and sprinkler
output relays
SPDT contacts, AgNi
Inductive (AC15) 250V / 2A
Resistive (AC1) 250V / 8A; 12A total return current
Fan variable output signal 0 … 10V; (3mA max)
Digital inputs
Volt free contacts 5V/0,1mA
Humidity
0 … 80% rh. non condensing
Protection class
IP65 (front protection with gasket)
Mounting
The EC2-742 can be mounted in panels with a 71 x
29 mm cutout. See dimensional drawing below for
space requirements including rear connectors.
Push controller into panel cutout.(1)
Make sure that mounting clamps are flush with
outside of controller housing
Insert allen key into front panel holes and turn
clockwise. Mounting clamp will turn and gradually
move towards panel (2)
Turn allen key until mounting clamp barely touches
panel. Then move other mounting clamp to the same
position (3). Tighten both sides very carefully until
controller is secured. Do not over tighten as
mounting clamps will break easily.
Electrical Installation
Refer to the electrical wiring diagram for electrical connections. A copy of this
diagram is labelled on the controller.
Use connection wires/cables suitable for 90°C operation (EN 60730-1).
EC2 analog inputs are for dedicated sensors only and should not be connected to
any other devices. Volt free digital inputs should only be connected to serial
control loops or relays with gold contacts. They should not be connected to any
other devices
Important:
Keep controller and sensor wiring well separated from mains wiring.
Minimum recommended distance 30mm.
Warning:
Use a class II category transformer for 24VAC power supply
(EN 60742). Do not ground the 24VAC lines. We recommend to use one
transformer per EC2 controller and to use separate transformers for 3
rd
party
controllers, to avoid possible interference or grounding problems in the power
supply. Connecting any EC2 inputs to mains voltage will permanently damage the
EC2.