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1 - SAFETY CONSIDERATIONS
1.1 - General
Installation, start-up and servicing of equipment can be hazard-
ous if certain factors particular to the installation are not con-
sidered: 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 servicing 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 separately, 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 (Internatio-
nal 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 uses and emits electromag-
netic signals. Tests have shown that the equipment conforms
to all applicable codes with respect to electromagnetic
compatibility.
RISK OF ELECTROCUTION: Even when the main circuit
breaker or isolator is switched off, certain circuits may still
be energised, since they may be connected to a separate power
source.
RISK OF BURNS: Electrical currents cause components to
get hot either temporarily or permanently. Handle power
cable, electrical cables and conduits, terminal box covers and
motor frames with great care.
2 - GENERAL DESCRIPTION
2.1 - General
PRO-DIALOG Plus is a system for controlling rooftop air
conditioners of the following types:
•
Single and dual circuit
•
Air conditioners and reversible heat pumps.
PRO-DIALOG Plus maintains room temperature at the setpoint
by controlling compressor start-up and optional components. It
controls operation of the indoor fan.
In cooling mode it controls the operation of the fans to maintain
the correct condensing pressure in each circuit. For heat pump
units it controls and optimises the defrost cycles of each circuit
in order to minimize the heating capacity reduction. Safety
devices are constantly monitored by Pro-Dialog to ensure unit
protection. Pro-Dialog 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).
•
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 Start/Stop 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 capabilities but does not offer any of the
features of the CCN network.
2.2 - Abbreviations used
In this manual, the refrigeration circuits are called circuit A and
circuit B. The compressor in circuit A is labelled A1, the one in
circuit B is labelled B1.
The following abbreviations are used frequently:
CCN : Carrier Comfort Network (the Carrier communication
network)
CCn
: Operating type: CCN
LED
: Light Emitting Diode
LOFF : Operating type: Local Off
L-On : Operating type: Local On mode
L-Sc
: Operating type: Local On following a time schedule
rEM
: Operating type: by remote contacts
SCT
: Saturated Condensing Temperature
SIO
: Sensor Bus (internal communication bus linking the
basic board to the slave boards)
SST
: Saturated Suction Temperature
tStA
: Operating type: by remote thermostat
TXV : Thermal Expansion Valve