KKT chillers vBoxX 10, Инструкция по эксплуатации

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The condenser fan is released if:

the compressor is running.
 No fault is queued at the motor protection switch.
 No fault is queued at the digital fault input (e.g. control device group fault).
When the system is switched on the primary pumps switch on after a 3.5 s time delay.
When the primary pump is switched on a timing element starts for each pump, which activates
monitoring of the minimum and maximum cold water pressure at the pump outlet. When the pump
is switched on a timing element for release of the compressor temperature control also starts. The
temperature control for the compressor is released if the time of a pump has expired. This time is
also used for activation of the flow monitoring.
The pressure and flow monitoring takes place with two timing elements:
 Delay on starting; the pressure or flow monitoring triggers an alarm if no pressure has
built up after the time has expired
 Delay during operation, in order to ignore short-term pressure or flow fluctuations, the
alarm is delayed.
On switching off the system the temperature control is locked immediately and therefore the
compressor is switched off. The pump continues running to prevent uncontrolled re-evaporation.
8.7.3. Cold water flow temperature control
The sensor in the tank is usually used to control the liquid flow temperature (system with tank, with
pump). If this sensor fails, the control system switches internally to the sensor in the cold water
return and the setpoint is increased by a defined value.
A PI controller is used, which generates an output signal of output signal of 0% up to 100%, which
activates the compressor.
The following operating states reduce the activation signal for the compressor:
 High pressure
 Low pressure

Difference between high and low pressure too large