Emerson Process Management user manual EC2-352 Display Case and Coldroom Controller, Mounting

EC2-352 Display Case and Coldroom 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 EC2-352 is a dedicated refrigeration controller with superheat and a driver for an Alco Controls Electric Control Valve EX2. In addition the EC2-352 controls air temperature and manages defrost and fan(s).

Network

6	4
8	5	1
		2
9	3
7

A PT5 pressure transmitter (1) and an ECN-Pxx pipe temperature sensor (2) measure saturated suction gas pressure and suction gas temperature at the evaporator outlet and feed the signals into the superheat control loop. The superheat controller output modulates the opening of the EX2 pulse width modulated Electrical Control Valve (6) thus optimizing the refrigerant mass flow through the evaporator. The ECN-Sxx air temperature sensors (3) and (4) measure air-in and out temperature of the evaporator and feed signals into the air temperature thermostat. The ECN-Fxx fin sensor (5) is used for defrost termination. The controller has 3 relay outputs to control the compressor (7), defrost heater (9) and evaporator fan (8). Please consult the technical data (right) for input and output ratings.

In case of power loss, due to the positive shut-off characteristics of the EX2 Electrical Control Valves, a liquid line solenoid valve is not needed to prevent flooding of the compressor.

!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

EC2 Series Controller

Power supply		24VAC ±10%; 50/60Hz; Class II
Power consumption		20VA max including EX2
Communication		TCP/IP Ethernet 10MBit/s
Plug-in connector size		Removable screw terminals
		wire size 0.14 … 1.5 mm2
Temperature
storage		-20 … +65°C
operating		0 … +60°C
Humidity		0…80% r.h. non condensing
Protection class		IP65 (front protection with gasket)
Pressure transmitter input		24VDC, 4...20mA
Output relays	(3)	SPDT contacts, AgCdO
		Inductive (AC15) 250V/2A
		Resistive (AC1) 250V/8A; 12A total return current
Triac output for EX2		24V AC, 0.1 … 1A
Electrical Control Valve
Coil (ASC 24V only)
Marking

Mounting

The EC2-352 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 lugs are flush with outside of controller housing

Insert allen key into front panel holes and turn clockwise. Mounting lugs will turn and gradually move towards panel (2)

Turn allen key until mounting lug barely touches panel. Then move other mounting lug to the same position (3)

Tighten both sides very carefully until controller is secured. Do not over tighten as mounting lugs will break easily.

Electrical Installation

Refer to the electrical wiring diagram (below) for electrical connections. A copy of this diagram is labeled 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. Connecting any EC2 inputs to mains voltage will permanently damage the EC2.

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 3rd 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.

EC2-352_65117_EN_R05.doc Replacement for Rev.:04 1 / 4 PCN : 864 925 16.09.2009