GE FVP110, Руководство по обслуживанию

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111
Block Modes
Actions of the FVP110 During
RCas mode Remote Cascade mode. In RCas mode, the function block per-
forms the specified calculations based on the setpoint that is
input from host computer or others via the remote cascade
parameter, and outputs the result.
Table 27 shows examples of block mode combinations in a
FVP110. When a block changes mode or the data status of a
signal changes for some reason, the other blocks connected to
that block identify the change by detecting the change in status
of an input signal, and change their modes, too. For example,
when the data status of BKCAL_IN in a PID block changes to
bad, the PID block automatically changes mode to IMan to ini-
tialize the control of its downstream block.
The respective modes that each block enters on occurrence of
a communication error and at a restart, and the handling of sig-
nals in each mode can be defined in the block’s option parame-
ters such as IO_OPTS and STATUS_OPTS. For details, see
the detailed descriptions of each function block.
Table 27 Examples of Block Mode Combinations and Operation Statuses
Operation Statuses AI PID AO TB
Transducer Initial setup, valve setup (when
carrying out auto tuning, travel calibration,
etc.)
- - O/S O/S
Modification of parameter settings in
transducer block (modification of control
parameter settings, etc.)
- - O/S O/S
Constant valve position control - - Auto Auto
PID single-loop control Auto Auto Cas Auto
PID cascade-loop control
Auto
Primary PID:
Auto
Secondary
PID: Cas
Cas Auto