Uniflair UST500, Инструкция по эксплуатации

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UST500 CONTROL BOARD
58 06MC0074@00B0100
14/04/2010
Start defrost
Defrost is started by temperature or pressure via a probe that can be selected in parameter dF12 -“Select probe to enable interval count
between defrosts”.
Pressure (or temperature) values for start defrost are given by:
•
start defrost: parameter dF01 Setpoint to enable interval count between defrosts
•
If the temperature/pressure of the probe configured as start defrost falls below the value set in dF01 (Setpoint to enable interval
count between defrosts and the compressor is ON*, the count defined indF03 (Cumulative interval between defrosts);
N.B.: In the event of a probe error, defrost will start as defined in dF03
•
When the duration defined in dF03 is reached, the device will start the defrost process.
•
At this stage, if dF04 - compressor - valve - compressor delay before start defrost = 0, then the compressor stays on. Otherwise,
the adjustment illustrated in the diagram below is performed:
*one compressor in single compressor machines, at least one compressor in twin compressor machines
This delay prevents any liquid from returning to the compressor.
In machines configured with two compressors, during defrost the compressors (steps) are both on.
This does not happen if one of the compressors is in alarm.
During this cycle, compressor safety timings are ignored.
Count mode
•
The time count between defrosts is suspended when the temperature/pressure falls below the value set in dF02-Setpoint to enable
interval count between defrosts) or when the compressor is switched off (one compressor in single compressor machines and at least
one compressor in twin compressor machines).
•
The count is cleared after one of the following events:
o
A defrost cycle is run.
o
A power failure.
o
Change of operating mode.
The time count is also cleared when the temperature/pressure rises above the value set in dF14 - Setpoint to clear cumulative interval
between defrosts
Start defrost temperature offset
In particularly dry and cold climates, the start defrost temperature will be different from the actual temperature that the external battery is
exposed to. The following regulator will directly offset the start defrost temperature/pressure by adding negative or positive values depending on
the external temperature.
The regulator is active when:
•
Activation parameter dF08 - Enable defrost dynamic differential = 1
•
A probe (analogue input) has been configured as external probe.
Start defrost
diagram
dF04
ON
OFF
ON
OFF
COMPR
RV
dF04
SD - Start Defrost
Time
Time