3
1 - SAFETY CONSIDERATIONS
1.1 - General
Installation, start-up and servicing of equipment can be
hazardous if certain factors particular to the installation are
not considered: operating pressures, presence of electrical
components and voltages and the installation site (elevated
plinths and built-up up structures). Only properly qualified
installation engineers and highly qualified installers and
technicians, fully trained for the product, are authorised to
install and start-up the equipment safely. During all servic-
ing operations all instructions and recommendations which
appear in the installation and service instructions for the
product, as well as on tags and labels fixed to the equipment
and components and accompanying parts supplied sepa-
rately, must be read, understood and followed.
• Apply all standard safety codes and practices.
• Wear safety glasses and gloves.
• Use the proper tools to move heavy objects. Move units
carefully and set them down gently.
1.2 - Avoid electrocution
Only personnel qualified in accordance with IEC (Inter-
national Electrotechnical Commission) recommendations
may be permitted access to electrical components. It is
particularly recommended that all sources of electricity to
the unit be shut off before any work is begun. Shut off the
main power supply at the main circuit breaker or isolator.
IMPORTANT: This equipment conforms to all applicable
codes regarding electromagnetic compatibility.
2 - GENERAL DESCRIPTION
2.1 - General
Pro-Dialog is an electronic control system to regulate units
of the following types: 61AF
These units have only one refrigerant circuit.
The Pro-Dialog control regulates:
•
compressor start-up to control the water loop
•
the fans to optimise operation of each refrigerant
circuit
•
the defrost cycles to ensure the operation of the
refrigerant circuit.
As standard Pro-Dialog offers three on/off commands:
•
Local - on/off command using the keyboard
• Remote - wired on/off command using volt-free
contacts
• Network - Carrier Comfort Network (CCN) on/off
command.
The command type is selected in advance by keyboard.
2.2 - Abbreviations used
In this manual, the compressors are labelled A1 and A2.
The following abbreviations are used frequently:
CCN
Carrier Comfort Network
LED
Light Emitting Diode
LEN
Internal communication bus linking the main
board to the slave boards
SCT
Saturated condensing temperature
SST
Saturated suction temperature
EXV
Electronic expansion valve
PD-AUX Auxiliary input/output board
3 - HARDWARE DESCRIPTION
3.1 - General
The control system consists of an NRCP2-BASE board
(that can control up to two compressors), a PD-AUX board
(that allows control of the different electric heater stages),
an EXV board (that ensures the control of the EXV
function) and a user interface. Certain options may require
a number of additional PD-AUX boards.
All boards communicate via an internal LEN bus. The
NRCP2-BASE board contains the complete control
program for the machine, and continuously manages the
recovery of the values of the various temperature and
pressure sensors.
The user interface includes an alphanumeric eight-line
display, two LEDs, five navigation keys and a contrast
control wheel.
