the system is functioning normally. The respective contacts will close when the unit is shut down on
a unit fault, or locked out on a system fault. For modular applications, the master unit will not only
output internal fault, but also the fault of subordinate units. Field connections are at XTB2 terminals
23 to 24.
Remote Start/ Stop Contacts
To remotely start and stop the unit, dry contacts can be wired to XTB2 terminals 80G to 87. Refer to
unit wiring diagram.
The function will be available after being activated through HMI.
Remote Cooling/ Heating Switch
The contacts are used to switch unit operating mode remotely.
Dry contacts can be wired to XTB2 terminals 80F to 86. Refer to unit wiring diagram.
The function will be available after being activated through HMI.
Flow Switch Input
For modular combinations, it is recommended to install an additional flow switch in outlet main pipe.
The switch is to be wired to terminals 80E
– 85 of XTB2 located in the control panel, as shown on the
unit wiring diagram.
External Interlock
The unit will be allowed to run only if the interlock is connected. It is used to link external facilities like
fire alarms in case there’s an emergency cutoff. It is wired to terminals 80H - 88 on block XTB2.
Make sure External Interlock is short-circuited or is linked to external facilities before operation.
COMPRESSOR HEATERS
Compressor heaters are standard. All compressors utilize two heaters with 40 W each.
If the unit is powered on for the first time, the crankcase heaters must be energized for at least 8 hours
prior to restarting a compressor. This will assure that liquid slugging and oil dilution does not damage
the compressors on start.
PRESSURE CUTOUT
One high pressure cutout and two low pressure cutouts (one LP cutout for cooling only unit) are
installed in the discharge and suction piping of each system. The HP cutout opens at 4.03 MPa (585
PSIG) and closes at 3.1 MPa (450 PSIG). The cooling LP cutout opens at 0.3 MPa (44 PSIG) and
closes at 0.5 MPa (73 PSIG). The heating LP cutout opens at 0.15MPa (22 PSIG) and closes at 0.3
MPa (44 PSIG).
WIRE CONTROLLER
Dual HMI is available on YCAE. Once the function is activated, the chip will automatically overwrite
the memory by the latest settings sent from either of the controllers.
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz
