dixell xweb 5000, Руководство по эксплуатации

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XWEB5000 Operation Manual
82/115 1592010600
The C.R.O. to better manage the availability of the refrigeration power, it modifies the set-point of the normal
temperature compressor rack controller. Execution interval set when the new set-point will be applied to the
compressor rack. Back analysis interval set how far in the past the analysis must retrieve its data. Defrost
check interval can be used as a check if the controllers really defrost. If there is no defrost for a period of
longer than this parameter, the C.R.O. will add a warning to the graph report.
Reference class is the group of controllers involved in the data analysis of the worst case. Controller is the
device made by Dixell that controls the compressor rack. Set point let the user choose the right set-point
(usually the suction set-point). The parameter for the worst case calculation (represented in percentage), let
the user define a threshold for the C.R.O.: below the value there is no action, above the algorithm sends the
new set-point. Dead band is set across the worst case set parameter and defines a neutral band: here inside
no action is starter. The algorithm to modify the suction pressure needs to know the initial value of this figure.
The Initial pressure parameter is used to set this value. Min./Max. suct. Press. Parameters are security limits
for the C.R.O. We strongly suggest to add this entries to prevent the algorithm to set set-point values out of
bound. Release and Call gain parameters control the new set-point value according to the following formulas.
If the real-time percentage is below the one setup in worst case set (dead band is computed), the new set-
point is:






   
1000
%
gain
old new
RLS
Set Set
 
%
(real-time percentage)
– (worst case set percentage)

gain
RLS
release gain
If the real-time percentage is above the one setup in worst case set (dead band is computed), the new set-
point is:






   
1000
%
gain
old new
CALL
Set Set