CIAT POWERCIAT2 LX, Инструкция по эксплуатации

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EN - 29 NA13.47 B
10.4 Control and safety devices
All of the unit's safety devices are managed by the
electronic circuit board in the
Xtraconnect 2 module. If
a safety device trips and deactivates the unit, look for the
fault, reset if necessary and clear the fault using the RESET
button on the console.
The unit will restart when the minimum time required by the
short-cycle protection elapses.
To find out the setting values of the various safety devices
and the fault clearance procedures, refer to the manual for
the
Xtraconnect 2 control module.
Low pressure (LP) sensor
Each refrigeration circuit is equipped with an LP sensor.
Located on the compressor intake, this sensor enables the
user to view the LP value and allows the control module
to provide a safety function by ensuring that the LP value
does not fall below the fault threshold parameter. If it
does fall below the setpoint value, the compressor for the
refrigeration circuit concerned is powered off and an LED
lights up on the console.
Triggering: 0.3 bar (relative).
High pressure (HP) sensor
Each refrigeration circuit is equipped with an HP sensor.
Located on the compressor discharge, it enables the user
to view the HP value and allows the control module to
provide a safety function by operating the fans.
High pressure (HP) safety pressure switch
The HP safety pressure switch is the main safety device
for the unit during operation. Each refrigeration circuit
is equipped with two HP pressure switches connected
in series. When the HP value exceeds the preset value
of the pressure switch, power to the compressor in the
refrigerating circuit concerned is cut off and the fault is
indicated by an LED on the control console.
The HP pressure switches are reset manually, thus any
fault will be cleared by resetting the pressure switch and by
pressing the RESET button on the console.
Triggering: 20.5 bar (relative).
Evaporator frost protection sensor
The evaporator is protected against freezing by two probes:
- A sensor on the evaporator's chilled water outlet
monitors the temperature of the fluid to be cooled.
If this temperature falls below the value set on
the controller, the machine is powered off and the
fault is indicated by an LED on the control console.
This probe acts as a safety device and must therefore
never be moved by the customer.
- A freon sensor monitors the temperature of the refrigerant
at the evaporator inlet. If this temperature falls below the
set value in the regulator, power to the compressor in
the refrigerant circuit concerned is cut off and the fault is
indicated by an LED on the regulator console.
The LP sensor and the exchanger water outlet sensor
ensure permanent monitoring to prevent any damage to the
exchanger. If the values of these two sensors become too
divergent, the circuit concerned shuts down and the fault is
indicated by a message and the illumination of a red LED
on the console.
Overpressure protection
Each refrigeration circuit in each unit is equipped with a
device that protects it against the risk of overpressure
resulting from fire:
- Safety valves. These protect the HP and LP circuits
against overpressure caused by an increase in the external
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This valve is not considered to be a safety accessory
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equipment directive.
- Maximum authorised pressure (PS) on the LP side:
The LP value (indicated on the data plate) corresponds
to the situation of the unit when powered off. This
value is given according to the pressure/temperature
ratio with an outdoor temperature of 65°C.
This temperature corresponds to the least favourable
situation to which the unit could be subjected, excluding
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Evaporator water circulation controller
This component has a safety function. It is mounted on
the chilled water outlet pipe and controls the circulation
of the water in the evaporator.
If this is not sufficient, the machine is shut down and an
LED lights up on the console.
Internal compressor protection
The compressors are equipped as standard with the SE-E1
protection module. The module has 3 control functions.
1. Temperature control for the motor (PTC sensor in the
winding), discharge gas and oil.
2. Rotation direction control.
3. Phase fault control.
If there is a fault, the circuit concerned is shut down and
an LED lights up on the console. The reset is performed
manually (once the winding has cooled) by interrupting
the L/N supply voltage for at least 5 seconds.
R1 : Oil heating
R2 : Oil temperature sensor (PTC)
Wire colour: 1 = black, 2 = brown, 3 = blue
Electronic expansion valve
The main controller is installed in the end cabinet.
All the expansion valve operating parameters are preset,
including evaporator superheating (7K). No adjustments
can be made.
The backup battery in this cabinet has a service life of 4
years. It allows the expansion valve to be closed in the
event of a power failure.
IMPORTANT : the valve must not be forced open when
there is no refrigerant flow. When the system is powered
off or evacuated, the start-up potential-free (dry) contact
must remain open.
Discharge sensor
Each unit includes one discharge sensor per refrigerating
circuit as standard. This sensor, which is located on the
discharge piping, enables the user to view the discharge
temperature value and allows the control module to provide
a safety function.
If the discharge temperature value exceeds the maximum
temperature threshold set in the control module, the
refrigeration circuit operates according to certain sequences
or shuts down the circuit concerned, with an indication on
the console.
Setting the compressor capacity
The compressors are equipped with dual control. Continuous
power control (pulsing of the magnetic valves to move the
slide) is used to adjust the cooling power as required,
and staged control is used to activate and deactivate the
compressor.