Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) PID and Ramp/Soak Functions - Manual (Page 17)

Continuous Control Functions
PID CONTROL BLOCK
2-11
Error Checks
If a calculation error occurs in the PID calculation, and the set qualities bad attribute is TRUE,
then the output qualities (output and track status) are set BAD. The PID calculation will be
initialized when qualities become good again.
In a cycle where the PID outputs have been previously marked BAD, but can now be
successfully calculated (required inputs are good), and the controller mode is AUTO or
CASCADE, the PID algorithm will initialize using the present output value. It is recommended
that the application design provide logic ’downstream’ of the PID block to set a track signal
when the PID qualities go bad. This way, the PID block will initialize from the track value
when it is again capable of executing, which would most likely be the preferred method of
initialization.
2.2.2 PID Control Block Parameters
The mnemonics, valid values, and data types for all fields that may be selected for display
and/or be used in making softwiring connections are listed in Table 2-1. The following further
defines the PID Control block configuration parameters.
Block Type
PID
This is the PID Control block type and is configured on the Function
Block Selection page.
Occurrence
1 to 4096
There may be up to 4096 ‘instances’ allowed of the PID block type.
Table 2-1. PID Control Block Attributes, Valid Values, Mnemonics, and Data Types
Field Name / Attribute Mnemonic Valid Values CWR Data Type Attr
Version VERSION 1 – – R Long State 00
Block Length BLKLEN – – R Count 01
Block State STATE RUN, HOLD, OFF, DEBUG CWR Short State 02
Bad Inputs Accepted BADINP NO(0), YES(1) CWR Discrete 03
Diagnostic Group SUPPGRP NONE, 1, 2, 3, 4, 5, 6, 7 CWR Long State 04
Calculation Error CERRS ENABLE(0), SUPPRESS(1) CWR Discrete 05
Calc. Error Unacked CERRU NO(0), YES(1) – WR Discrete 06
Calc. Error Unacked Quality CERRUQ GOOD(0), BAD(1) – WR Discrete 07
Calc. Error Active CERRA NO(0), YES(1) – WR Discrete 08
Calc. Error Active Quality CERRAQ GOOD(0), BAD(1) – WR Discrete 09
Output Calculation Error OPCERRS ENABLE(0), SUPPRESS(1) CWR Discrete 10
Output Calc. Error Unacked OPCERRU NO(0), YES(1) – WR Discrete 11
Output Calc. Error Unacked Q OPCERRUQ GOOD(0), BAD(1) – WR Discrete 12
Output Calc. Error Active OPCERRA NO(0), YES(1) – WR Discrete 13
Output Calc. Error Active Q OPCERRAQ GOOD(0), BAD(1) – WR Discrete 14
Control Interval CI Msec Time Value CWR Msec Time 15
Setpoint Modes Allowed SPMA L(1), R(2), L.R(3) C – R Count 16
Setpoint Mode Status,
Initial Value SPMS LOCAL(0), REMOTE(1),
TRACK(3)*, FAULT(5)* CWR Short State 17
Setpoint Mode Status Quality SPMSQ GOOD(0), BAD(1) – WR Discrete 18
Setpoint Mode Command SPMC LOCAL(0), REMOTE(1) – – R Short State 19
Setpoint Track Enable SPTE NO(0), YES(1) C – R Discrete 20