T-CU19-JAN24-1
Page 14
Commissioning
Before performing any service/maintenance
work on the unit, ensure that the power
supply is switched off and then wait at least
5 minutes to allow the capacitor to fully
discharge. Failure to do so may result in
serious injury or death.
To gain access to the electrical box, turn the mains isolator
switch on the front of the unit to the OFF position, loosen the
screws on the left-hand side of the door and open the door.
The electrical box is located behind the front door. Remove
the screws in the electrical box cover to access components.
Figure 9: Access Point
Access to Controller and LCD
Display
Only Authorized personnel are allowed to
access the controller and LCD display.
Please wait approximately 1 minute for
controller initialization after switching on the
main isolator.
Pre startup checks
Before starting the condensing unit, the following checks
should be carried out as a minimum:
•
Check electrical supply is correct and all connections
are sound.
•
All moving parts are free, and guards are fitted.
•
Compressor oil level satisfactory.
•
LCD display cable is connected to the controller to
enable settings.
•
Change the required setting to suit the type of
application. Else, maintain as factory default setting for
medium temperature application.
•
All valves are in correct operating position.
•
Initial refrigerant charge through liquid line.
•
Crankcase heater energized for a minimum of 12 hours
before compressor start-up.
•
Gauge manifold connected to both low and high sides
of system.
Table 11: Factory Default Setting
Description
Factory Default
Setting
Remark
Refrigerant
preset on
controller
R448A
Type of refrigerant
available for
selection: R448A,
R449A, R404A
Low
Pressure
Switch
Cut In: 3barg,
Differential:
2barg (Auto
Reset)
To cut off compressor
when suction pressure
drops below 1barg
* Software low
pressure alarm
threshold 1.2barg
(Cae26)
High
Pressure
Switch
Cut Out:
28barg,
Manual Reset:
22barg
Manual reset on the
cartridge type high
pressure switch is
required after the
fault is removed.
Unit Status
On/Off on
keyboard
Off position
Must log in through
service or
manufacturer
password to turn on
the unit
Crankcase
Heater
Activation
Activated only
when by
regulation
and/or alarm
Compressor crankcase
heater will be
activated when
compressor off and
external temperature
is below 15
0
C.
(Cag43, Cag44)
Condenser
Fan
Modulation
Setpoint:
16barg,
differential:
3barg,
Proportional.
Cut In only
when
compressor is
turned ON
Fan starts to rotate
when compressor is
turned ON and
discharge pressure
more than 13barg.
Fan runs at full speed
when pressure more
than 19barg.
The unit is equipped with an electronic
controller and frequency converter, which
had been pre-programmed with parameters
ready for use with the actual unit.
Parameters for operation with refrigerant
R448A is defaulted. The parameter needs to be changed
if another refrigerant is to be used (Refer to Refrigerant
Selection).
Enter password to access controller settings.
Please see page 15 for different access level
passwords.
Before running the unit, the controller settings for
Refrigerant Selection
(refer
Page 16)
should be
checked/altered as required:
Running the unit
•
Switch unit on by controller (refer
Page 16
).
•
Run the unit and check compressor and condenser fan
operation.
•
Check system pressures and temperatures, gas charge
and running currents of unit to ensure correct operation.
•
Check transducer / sensor readings are accurate
(calibrated equipment required).
