Publication 1763-RM001C-EN-P - October 2009
292
Process Control Instruction
Zero Crossing Deadband (ZCD)
The deadband extends above and below the setpoint by the value
entered. The deadband is entered at the zero crossing of the process
variable and the setpoint. This means that the deadband is in effect only
after the process variable enters the deadband
and
passes through the
setpoint.
The valid range is 0 to the scaled maximum, or 0 to 16,383 when no
scaling exists.
Feed Forward Bias (FF)
The feed forward bias is used to compensate for disturbances that may
affect the CV output.
Scaled Error (SE)
Scaled error is the difference between the process variable and the
setpoint. The format of the difference (E = SP-PV or E = PV-SP) is
determined by the control mode (CM) bit. See Control Mode (CM) on
page 293.
Tuning Parameter
Descriptions
Address
Data
Format
Range
Type
User Program
Access
ZCD - Zero Crossing
Deadband
PD10:0.ZCD
word (INT) 0 to 32,767
control
read/write
Tuning Parameter
Descriptions
Address
Data
Format
Range
Type
User Program
Access
FF - Feed Forward
Bias
PD10:0.FF
word
(INT)
-16,383 to +16,383
control
read/write
Tuning Parameter
Descriptions
Address
Data
Format
Range
Type
User Program
Access
SE - Scaled Error
PD10:0.SE
word (INT) -32,768 to +32,767
status
read only
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