Riello 20120391, Инструкции для установщика и технической поддержки

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CONTROL PANEL
INSTALLATION
3 CONTROL PANEL
3.1 Acronyms/abbreviations
The table below lists the abbreviations used in this section.
Cooling circuits are identified with "circuit A" and "circuit B".
A1, A2, A3 Compressors of circuit A
B1, B2 Compressors of circuit B
BMS Building management system
DGT Discharge gas temperature
DHW Domestic hot water
EHS Electric heater stage
EXV Electronic expansion valve
FC Free cooling
LED Light Emitting Diode
LEN
Sensor bus (internal communication
bus connecting master board to slave
boards)
Local-Off/LOFF Operation type: Local Off
Local-On/L-C Operation type: Local On mode
Local-Schedule/L-
SC
Operation type: Local On following a
time schedule
Master mode/Mast
Operation type: Master unit (master/
slave unit)
Network mode/Net Operation type: Network
Remote mode/Rem Operation type: Remote contacts
OAT External air temperature
SCT Saturated condensing temperature
SST Saturated suction temperature
EWT Entering water temperature
LWT Leaving water temperature
3.2 Controls overview
3.2.1 Control system
R
NXC-NXH devices are equipped with Connect Touch con-
trol used as user interface and configuration tool for commu-
nication devices.
Connect Touch can work as a stand-alone system or can be
connected to the building management system using the fol-
lowing communication systems: Modbus TCP/IP, BACnet/IP or
Lon communication.
The units can be equipped with standard fixed speed fan con-
trol system or with optional variable speed fan drives, able to
reduce energy consumption during runtime and downtime,
to provide condensing or evaporation pressure control and to
regularly start the fan.
The system can control fixed speed pumps or variable speed
pumps of both for chillers and heat pumps with a hydronic
module.
9
This section might refer to some accessories not available
for the devices of the
R
NXC-NXH series.
Hybrid system
The Connect Touch control allows producing hot water by
means of a boiler. This solution is necessary with low out-
side temperature; the boiler works as hot water source for the
air-conditioning system or, according to the configuration, as
domestic hot water (DHW) generator.
The latter configuration can be activated by
R
Technical
Support Service only.
3.2.2 Operating mode
The system controls the starting of the compressors required
to maintain the desired temperature of the water entering or
leaving the heat exchanger. It manages the constant operation
of the fans to keep the correct refrigerant pressure in each cir-
cuit, it controls the safety devices to protect the unit against
faults and ensures its proper operation.
The control can operate according to three independent modes:
− local mode: the unit is controlled through the com-
mands sent with the user interface
− remote mode: the unit is controlled through dry con-
tacts
− network mode: the unit is controlled from the network
controls (Modbus). Use the data communication cable
to connect the unit to the RS485 communication bus.
When the control operates independently (local or remote
mode), it keeps all its control capacities but it provides none of
the Network characteristics.
9
The emergency stop button in network operation mode
stops the unit regardless of the active operation type.