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2 - GENERAL DESCRIPTION
2.1 - General
PRO-DIALOG Plus is a system for controlling units which use
reciprocating compressors*:
•
Single or dual circuit
•
Air or water-cooled condensers
•
Non-reversible heat pumps
•
Split systems
* At present only air-cooled models are available.
PRO-DIALOG Plus controls compressor start-up and demand
limits needed to maintain the desired entering or leaving tem-
perature setpoint for water. It automatically sets the position of
the electronic expansion valve (if used) to optimise the evapo-
rator charge. It controls operation of the fans (on air-cooled
units) or water valves (on water-cooled units) to maintain the
correct head pressure in each circuit.
Safety circuits are constantly monitored by PRO-DIALOG
Plus to ensure safe operation of the unit. PRO-DIALOG Plus
also gives access to a Quick Test program covering all inputs
and outputs.
All PRO-DIALOG Plus controls can work in accordance with
three independent modes:
•
Local mode: the machine is controlled by commands from
the user interface.
•
Remote mode: the machine is controlled by remote
contacts (volt-free contacts, analogue signals).
•
CCN mode: the machine is controlled by commands from
the Carrier Comfort Network (CCN). In this case a data
communication cable is used to connect the unit to the
CCN communication bus.
The operating mode must be chosen with the Operating Type
selection button described in section 4.2.1.
When the PRO-DIALOG Plus system operates autonomously
(Local or Remote mode) it retains all of its own control capa-
bilities but does not offer any of the features of the CCN network.
2.2 - Abbreviations used
In this manual the circuits are called circuit A and circuit B.
The compressors in circuit A are labelled A1, A2, A3 and A4.
Those in circuit B are labelled B1, B2, B3 and B4. A1 and B1
are the lead compressors.
The following abbreviations are frequently used:
AI
- Analogue Input
AO
- Analogue Output
CCn
- Operating type: CCN
CCN
- Carrier Comfort Network.
This is the Carrier communication network
DI
- Discrete Input
DO
- Discrete Output
EXV
- Electronic Expansion Device
LED
- Light Emitting Diode
LOFF - Operating type: Local off
L-ON - Operating type: Local operation
MASt - Master unit operating type (master/slave assembly)
RCPM - Reciprocating Compressor Protection Module
rEM
- Operating type: by remote control contacts
SCT
- Saturated disCharge Temperature
SIO
- Standard Input/Output - internal communication bus
linking the basic board to the slave boards
SST
- Saturated Suction Temperature
