Relay is used to recognize the control switch condition and Current Transducer helps to change
Current value which is recognized by CT(Current Transformer) to signal that PLC can recognize.
HMI which has touch panel for user interface is installed to door of control panel, it indicates
power approval through power lamp.
Also, switch that can set body/remote and emergency stop switch is also installed.
n PLC and HMI Unit
HMI (Human Machine Interface) which is united with PLC(Programmable Logic Controller) is shown
in Fig. 10 described below, it is located in control panel Door. HMI is touch screen for convenient
Through touch screen interface, operator can check the chiller operation condition and controls in
detail. Control composition can be done through touch screen interface.
Chiller Water-cooled Screw
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