Honeywell Series A User Manual page 58

3. Fieldbus Integration With Experion System
3.3. Control Mode Interaction
For use within the Experion system, the structure of the MODE_BLK parameter is
expanded to add MODE to the existing Actual, Target, Permitted, and Normal modes as
outlined in the following table.
Control Mode
Structure
MODE
MODE.TARGET
MODE.ACTUAL
MODE.PERMITTED
MODE.NORMAL
The Experion system uses the name MODE instead of MODE_BLK and its enumeration
set is identical to that used in fieldbus. Mode is a write only parameter and the FIM will
reject all reads. The FIM captures all writes to MODE and maps valid changes to
MODE.TARGET. If the value NORMAL is written to the MODE.TARGET, the FIM
replaces it with the value from MODE.NORMAL. If a new MODE.NORMAL value is
entered, it is validated against the MODE.PERMITTED values. The OOS mode is not an
acceptable normal mode.
When a new MODE.PERMITTED value is entered, the FIM forces the OOS mode to be
permitted. Only a user with an access level of Engineer is allowed to put a block into its
OOS mode or to return the block to an operating mode. This means a user must have an
access level of Engineer to put a block in Man, Auto, Cas, Rcas, or Normal, if the blocks
current target mode is OOS. When a mode is changed, the FIM clears the
58 Experion PKS Series A Fieldbus Interface Module User's Guide
Data Type
Enumeration Write Only
Experion system style mode enumeration
MAN, AUTO, CAS, NORMAL, BCAS, NONE
Enumeration Read/Write
Target mode
OOS, MAN, AUTO, CAS, RCAS, ROUT
Enumeration Read Only
Actual Mode
OOS, IMAN, LO, MAN, AUTO, CAS, RCAS, ROUT
Bitstring Read/Write
Permitted mode
MAN, AUTO, CAS, RCAS, ROUT
OOS is always permitted
Enumeration Read/Write
Normal mode
MAN, AUTO, CAS, RCAS, ROUT
OOS is not Normal
Honeywell
Description
July 2010
R400