Flooded Type Water Cooled Screw Chiller Technical M
anual
50
5
Senso
r
It is a kind of electrical
element used to detect
temperature and pressure,
whose
physical
characteristics
vary
with
change (e.g. resistance of
NTC varies with change of
temperature) of temperature
and pressure.
2. Function and Control of Unit
2.1 Function and Control of Unit
Manually ON/OFF
By pressing “start” button on controller, unit starts after 5s; when it’s necessary to stop operation, by
pressing “stop” button, unit shuts down.
Timely ON/OFF
Users can set ON/OFF time in for of year, month and day, or set ON/OFF time for a week or set
ON/OFF time for every day. If user sets ON/OFF time, unit automatically starts and shuts down at the
set time.
ON/OFF Control Process of Unit
Electrify control cabinet and preheat oil heater of compressor. unit can be started after oil
heater is preheated at least eight hours;
During startup process, firstly start refrigeration/cooling water pump; after time is delayed for 60S,
unit begins to start. If water temperature exceeds set value plus 2
℃
, compressor starts; Compressor
operates at 25% at first and switches to operate at 50% 30S later, then loads according to
temperature.
In case of shutdown, unit unloads to 25% and shuts down after operating for 30 seconds. Stop
cooling and refrigeration water pump after time is delayed for 180S.
If cooling water pump isn’t interlocked with refrigeration water pump, it’s required to stop cooling and
refrigeration water pump after compressor stops and time is delayed for 180S in case of shutdown.
