Flooded type water cooled screw chiller (PCB Control)
32
III. Control
1.
Control flow chart
HMI+ Main base controller:
Main base controller gathers signals through input terminals, such as pressure,
temperature and the state of protection switches and ensures unit’s current
condition. At the same time, according to input signal from HMI, such as starting
signal, controller performs the logical operations and outputs signals. These
signals act on components, time relay, contactors and so on.
Ph
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Pro
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Miniature
Circuit
Breaker
M
~
Compressor
Thermorelay
Compressor
Contactor
Star-Delta Start
HMI
Terminal for
External Signal
e.g. Temp.
Pressure
Terminal for
Output Action
e.g. Solenoid
Valve
Main base controller
M
~
Compressor
Thermorelay
Compressor
Contactor
Star-Delta Start
380VAC
3P+N+PE
2 Compressors
Double-Head
