Figure 8.4 Pid Control Block - Flowserve Logix 3400IQ User Instructions

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Table 8.9 Honeywell PID Parameters
Parameter Name
ERROR_ABS
WSP
BLOCK_TEST
PID Block Diagram
Figure 8.4 is a block diagram showing the key components of the PID control function block.
FF_VAL
Setpoint
CAS_IN
SP_RATE_DN WSP
SP_RATE_UP
SP HI LIM
RCAS_IN
SP_LO_LM
SP
PV Filter
IN
PV_FTIME
Target &
Permitted
Mode Select
Mode
SHED_OPT
PID Block Description
PID control function block is an algorithm that produces an output signal in response to the
measured variable and the set-point. The PID function block allows the user to choose either a
standard PID control equation (Ideal) or a robust PID equation defined by Honeywell. This selection is
defined in the PID_FORM parameter.
The output has three terms: Proportional, Integral and Derivative. The output is adjusted by tuning
constants. Three tuning constants are contained in the ideal PID equation.
The robust PID uses four tuning constants.
1. GAIN is the tuning constant of the Proportional term.
2. RESET is the tuning constant of the Integral term.
Logix 3400IQ Digital Positioner FCD LGENIM3402-00 – 0/07
Description/Parameter Contents
Absolute value of the difference between PV and working set-point. (Read-
only parameter.)
Working set-point. This is the set-point value after absolute and rate limits
have been applied. Deviation alarms are computed on this value. (Read-
only parameter.)
An internal Honeywell test parameter.
Feed Forward
FF_SCALE
FF_GAIN
PV
Actual &
Normal
Mode

Figure 8.4 PID Control Block

BKCAL_IN
ROUT_IN
Bypass
BYPASS
Output
PID Control
OUT_ HI_LIM
GAIN
OUT_LO_ LIM
RESET
BAL_T IME
BAL_TIME
RATE
PID_FORM
ALGO_TYPE
OUT_LAG
GAIN_NLIN
GAIN_COMP
ERROR_ABS
Backward
Path Outputs
BKCAL_HYS
Output Track
Alarm
HI/LO
TRK_SCALE
DEV
TRK_IN_D
TRK_VAL
OUT
ROUT_OUT
RCAS_OUT
BKCAL_OUT