YME Engineering Course

I. REGULATORY CONTROL FUNCTION BLOCKS
To set the deadband action - Select “Yes” or “No.” The default is “No.” When the
deadband action is set as “Yes,” the hysteresis (HYS) must be set. Hysteresis:
Engineering unit data between 0 and the PV scale span range limit. The default
is the value equivalent to 1.0 % of the PV scale span.
♦ AUT Fallback
The AUT fallback is an error processing function that switches the block
mode from cascade (CAS) or primary direct (PRD) to automatic (AUT)
when the AUT fallback condition is established. Thus the set value of the
control loop can be set by the operator. The AUT fallback condition is
established when the data status of the cascade setpoint value (CSV)
become invalid (BAD) or communication error (NCOM).
♦ Computer Backup Mode
When the computer fail is detected, the function block suspends the action
in the remote cascade (RCAS) mode or remote output (ROUT) mode
temporarily and switches to the computer backup mode.
I.3.6 OUTPUT
♦ Output Change
The output velocity limiter limits the amount of change in the output value
according to the output velocity limit setting. The output velocity limit is a
permissible amount of output change over one scan period. The output
velocity limiter and the bypass for MAN-mode output velocity limiter can
be defined.
• Output Velocity Limiter:
Engineering unit data or percentage within the range from 0 to the
MV scale span setting in positive values only (six significant
figures). The default setting is 100.0 %.
• MAN Mode Output Velocity Limiter Bypass:
Selectable between “Yes” and “No.” Default is “No.”
♦ Auxiliary Output
The auxiliary output is used when output a signal through the SUB
terminal to a destination other than the final control element. The signal is
often used as compensation data to other function blocks, or to the
indicator outside of the FCS, etc. In the Regulatory Control Blocks, the
process variable (PV), change in process variable (∆PV), manipulated
output value (MV), or the change in manipulated output value (∆MV) is
output via the SUB terminal. The connection method is the data setting.
Output Type is selectable from “Positional Output Action” and “Velocity
Output Action.” Default is “Positional Output Action.” When the output
action for auxiliary output is set to “Positional Output Action,” the output
values (MV, ∆MV, PV, or ∆PV) can be set in the connection destination as
YME Training Center I-18
CS3KR3-ENG 1 ST Edition Jan 2002