Siemens SIMATIC S5-95F Manual page 262

Blocks and Their Functions
Data Word Name
11 STEU
12 YH
14 BGOG
16 BGUG
22
24
29 XZ
48 YA
All parameters (with the exception of the control word STEU) must be specified as 16-bit fixed point
numbers.
Caution
!
The PID algorithm uses the data words that are not listed in Table 9-5 as auxiliary flags.
Initialization and Call Up of the PID Controller in a STEP 5 Program
Several different PID controllers can be implemented by calling up OB251 repeatedly. A data block
must be initialized prior to each OB251 call up.
Note
Important controller data are stored in the high-order byte of control word DW11 (DL11).
Therefore make sure that only T DR 11/SU D11.0 to D11.7 or RU D 11.0 to D11.7
operations are used to modify user-specific bits in the control word.
9-8
Table 9-5. Format of the Controller DB (Continued)
Control word (bit pattern)
Value for manual operation (- 2047 to +2047)
Upper limit value (- 2047 to +2047)
Lower limit value (- 2047 to +2047)
Actual value (- 2047 to +2047)
X
Disturbance variable (- 2047 to +2047)
Z
Derivative time (- 2047 to +2047)
Output variable (- 2047 to +2047)
Comments
EWA 4NEB 812 6210-02
S5-95F