Emerson Vission 20/20, Руководство по эксплуатации и обслуживанию

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19 – 4
Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.9
Section 19 • Configuration
Compressor Control
Vilter compressors typically run in one of two control
modes, suction pressure or process temperature con-
trol, see Figure 19-2.
Suction Pressure Control:
• This de
fi nes the suction pressure input as the pro-
cess variable and all controls will be based on suction
pressure. The operator has the option to select up to
two controllers where each can have its own set of
setpoints.
Process Temp. Control:
• This de
fi nes the process temperature input as the
process variable and all controls will be based on the
process temperature. The operator has the option to
select up to two controllers where each can have its
own set of setpoints.
Optional Function Selection
The following options are additional features of the
Vission 20/20 that can be selected. Some of these op-
tions will not be available for selection unless the proper
I/O cards are installed and enabled, see Figure 19-2.
Compressor VFD:
• Enables the compressor motor VFD option.
% Slide Volume Position:
• Unused.
Economizer Pressure:
• Enables the economizer pressure input.
Suction Superheat Monitor:
• Enables the suction superheat safety algorithms.
Suction superheat monitor works only with R717 and
R507. Suction superheat monitor and Discharge su-
perheat monitor features are mutually exclusive.
Figure 19-2. Con fi guration Screen - Compressor Sequencing (Page 2)