CIAT AQUACIATPOWER CONNECT TOUCH ILD 602R, Инструкция по эксплуатации

Страница: 51 / 64

EN - 51 AQUACIAT
POWER
8 - STANDARD CONTROL OPERATIONS AND OPTIONS
8.16 Free Cooling (option 305A/B)
When the OAT is low enough compared to the control setpoint,
the controller allows the hydraulic Free Cooling (FC) system to
cool down the customer loop by circulating water in FC coils
which are located in parallel to MCHE refrigerant coils. This saves
energy in low outdoor air temperature conditions.
Option 305A: Total Hydraulic Free Cooling
(FC coils are mounted on each coil of two circuits).
Option 305B: Partial Hydraulic Free Cooling
(FC coils are mounted on coils of one circuit only).
Two 2-way valves are used to disable or enable the FC subset
upstream of the water exchanger.
The circuit of the unit mounted with FC coils can operate in
the following modes:
■ Mechanical Cooling (MC) mode (with compressors activated
only): When the FC conditions cannot be met.
■ Controlled Free Cooling mode (compressors stopped on both
circuits): When the FC conditions are met and sufficient to
achieve the control setpoint.
■ Full Free Cooling mode (compressors stopped on one circuit
but not on the other): When the FC conditions are met and
the other circuit has already some compressors ON. The
objective is to take advantage of the total FC power of the
circuit to accelerate the unloading of the compressors of the
other circuit.
■ Mixed mode (MC and FC at the same time): When the FC
conditions are met but not sufficient enough to achieve the
requested setpoint.
8.17 Defrost cycle (heat pumps only)
When the outside air temperature is low and the ambient
humidity is high, the probability of frost forming on the surface
of the outdoor coil increases. The frost covering the outdoor
coil may decrease the air flow across the coil and lead to lower
performance of the unit. To remove the frost from the coil, the
control initiates the defrost cycle when necessary (defrost mode
acts as Cooling mode).
8.17.1 Standard defrost
During the defrost cycle, the circuit is forced into the cooling
mode. The heat (energy) is extracted from the water circuit by
using compressors and reversing the 4-way valve. The defrost
cycle lasts until the end of defrost temperature is achieved.
8.17.2 Free defrost
Free defrost is used in order to eliminate a respectively small
amount of frost that has formed on the surface of the coil. Contrary
to the standard defrost session, in the case of the free defrost
session the heat (energy) is absorbed from the air. When running
the free defrost operation, fans are activated and all compressors
are turned off. The free defrost is most efficient when current
heating demand is below the heating capacity delivered by the
unit and the outside air temperature is above 1°C.
IMPORTANT: In the case of a large amount of frost covering
the coil, the standard defrost cycle will be started.
8.18 Master/Slave control
The CONNECT TOUCH control system optimises the
management of two units linked by the proprietary protocol
network.
The unit configured as the Master is a control point for the
master/slave assembly. The Master unit can be controlled
locally, remotely or by network commands, while the Slave unit
remains in Network mode.
All control commands sent to the master/slave assembly (start/
stop, setpoint selection, heating/cooling, operating mode, load
shedding, etc.) are handled by the unit which is configured as
the master. The commands are transmitted automatically to the
slave unit. For example, if the master chiller is turned off while
the master/slave function is active, then the slave unit will be
stopped.
In the event of a communication failure (between the two units),
each unit will return to an autonomous operating mode until the
detected fault is cleared. If the Master unit is stopped due to a
detected alarm, then the Slave unit is authorised to start.
IMPORTANT: Master/Slave assembly can be configured
only by service technicians.
8.19 BACnet IP option (option 149)
The BACnet IP communication protocol can be used to
communicate with other controllers available in the same BMS.
NOTE: This option requires the Software Activation Key.
8.20 Brine option (option 6)
AQUACIAT
POWER
LD units offer a cooler fluid type selection,
including standard water fluid as well as the optional brine fluid,
i.e. low brine (option 6). The brine option is commonly used
for low temperature applications. AQUACIAT POWER ILD heat
pumps can use water only.
NOTE: This option requires the Software Activation Key.
8.21 Refrigerant gas leak detection option
The control permits refrigerant leak detection. Two additional
sensors that detect the refrigerant concentration in the air must
be installed on the unit.
If one of these sensors detects an abnormal refrigerant level for
more than one hour (timer set by service technicians), the alarm
will be triggered, but the unit will continue to operate.
8.22 Modbus (option 149B)
The Modbus communication protocol is used by the building
management system or the programmable controllers to
communicate with the CONNECT TOUCH control.
NOTE: Modbus option is provided as standard.
8.23 Cooling floor optimization (option 119C)
Heat pumps with option 119C enabled will operate with lower
than standard capacity limits in Cooling mode in order to save
energy.
NOTE: This option requires the Software Activation Key.