Uniflair UST500, Инструкция по эксплуатации

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UST500 CONTROL BOARD
06MC0074@00B0100
14/04/2010
59
Decalibration of start defrost setpoint based on external temperature
The figure below shows how decalibration of the start defrost setpoint progresses based on
external temperature.
Positive offset Negative offset.
End defrost
End defrost can be controlled by temperature or pressure via
•
a probe that can be selected in parameter dF13 - “Select probe to end defrost”
•
and/or by Digital Input (in this case, a digital input must be configured as “End Defrost” (value ±22)
•
and/or by time, if the probe configured for the output fails.
Defrost will end when:
•
the temperature/pressure rises above dF02 - Deactivate defrost setpoint
•
the duration of the defrost reaches dF07 - Maximum defrost time
•
if the digital input configured as end defrost activates
at the end of defrost, if dF05 - Compressor - valve - compressor delay before the end of defrost = 0, the compressor stays on. Otherwise,
the adjustment illustrated in the diagram below is performed:
•
At the end of defrost, the compressor safety timings are ignored and the external exchanger heater fan is switched on at maximum
power for the time set in parameter dF06 - Dripping time= 0.
Defrost when compressor stops
If an alarm stops the compressor in single compressor machines or both compressors in twin compressor machines, defrost starts as a result of
this stop.
Manual defrost
UST500 can force defrost manually by pressing and holding the [UP] key.
Manual defrost is possible when:
•
dF00 - Enable defrost function = 1
•
UI10 -Enable defrost function from key
•
if the temperature / pressure of the external exchanger is less than the value set in parameter dF01 (Set point to enable interval
count between defrosts)
Defrost starts in the sequence described in the section “Start Defrost”.
•
The defrost LED is blinking.
End defrost takes place as described in the section “End Defrost”.
Power failure during defrost.
If a power failure happens during defrost, the procedure will be cancelled. All timings will be cancelled and restarted.
Decalibration of
start defrost
setpoint based on
external
temperature
End defrost
diagram
dF05
ON
OFF
ON
OFF
COMPR
RV
dF05
ED - End of Defrost
Time
Time
dF11 < 0
dF10
dF09 > 0
Temp
dF10
dF09 < 0
Temp
dF11 > 0 dF11 < 0 dF11 > 0