PID Loop Operation
Maintenance
and Troubleshooting
8–8
PID Loop Operation
The parameters associated with each loop are listed in the following table. The
address offset is in octal, to help you locate specific parameters in a loop table. For
example, if a table begins at V2000, then the location of the reset (integral) term is
Addr+11, or V2011. Do not use the word# (in the first column) to calculate addresses.
Word # Address+Offset Description Format
1 Addr + 0 PID Loop Mode Setting 1 bits
2 Addr + 1 PID Loop Mode Setting 2 bits
3 Addr + 2 Setpoint Value (SP) word/binary
4 Addr + 3 Process Variable (PV) word/binary
5 Addr + 4 Bias (Integrator) Value word/binary
6 Addr + 5 Control Output Value word/binary
7 Addr + 6 Loop Mode and Alarm Status bits
8 Addr + 7 Sample Rate Setting word/BCD
9 Addr + 10 Gain (Proportional) Setting word/BCD
10 Addr + 11 Reset (Integral) Time Setting word/BCD
11 Addr + 12 Rate (Derivative) Time Setting word/BCD
12 Addr + 13 PV Value, Low-low Alarm word/binary
13 Addr + 14 PV Value, Low Alarm word/binary
14 Addr + 15 PV Value, High Alarm word/binary
15 Addr + 16 PV Value, High-high Alarm word/binary
16 Addr + 17 PV Value, deviation alarm (YELLOW) word/binary
17 Addr + 20 PV Value, deviation alarm (RED) word/binary
18 Addr + 21 PV Value, rate-of-change alarm word/binary
19 Addr + 22 PV Value, alarm hysteresis setting word/binary
20 Addr + 23 PV Value, error deadband setting word/binary
21 Addr + 24 PV low-pass filter constant word/BCD
22 Addr + 25 Loop derivative gain limiting factor setting word/BCD
23 Addr + 26 SP value lower limit setting word/binary
24 Addr + 27 SP value upper limit setting word/binary
25 Addr + 30 Control output value lower limit setting word/binary
26 Addr + 31 Control output value upper limit setting word/binary
27 Addr + 32 Remote SP Value V-Memory Address Pointer word/hex
28 Addr + 33 Ramp/Soak Setting Flag bit
29 Addr + 34 Ramp/Soak Programming Table Starting Address word/hex
30 Addr + 35 Ramp/Soak Programming Table Error Flags bits
31 Addr + 36 PV direct access, channel number word/hex
32 Addr + 37 Control output direct access, channel number word/hex
Loop Table
Word Definitions
To Next Page
Loading...
Need help?
General
