Link And Block Schedules; Link Active Scheduler (Las) And Link Master - Honeywell Series A User Manual

3. Fieldbus Integration With Experion System

3.4. Link and Block Schedules

Element and Bit
GRANT_DENY.GRANT:0
GRANT_DENY. GRANT:1
GRANT_DENY.GRANT:2
GRANT_DENY.GRANT:3
GRANT_DENY.DENY:0
GRANT_DENY.DENY:1
GRANT_DENY.DENY:2
GRANT_DENY.DENY:3
The Grant selections are mutually exclusive. If you select Program Operations, the Local
Operations selection is turned off. If Local Operations is selected, neither an operator nor
a high level device (program) has the right to modify a parameter value of the block.
Note that access by another function block is always granted and is independent of
GRANT_DENY selections. Also, an operator can always change the MODE of a block
with Program or Local Operations Granted. When an operator changes the MODE, it
automatically resets all four Grants to off.
The GRANT_DENY parameter will not track the mode of an associated SCM.
3.4 Link and Block Schedules

Link Active Scheduler (LAS) and Link Master

All links must have a Link Active Scheduler (LAS). The LAS operates at the data link
layer as the bus arbiter for the link. It provides the following functions.
64 Experion PKS Series A Fieldbus Interface Module User's Guide
Attribute
Program Grants permission to higher level
Operations device to change the target mode, set
point or output of a block, depending
on block mode.
Tune Grants permission to higher level
device to change tuning parameters of
the block.
Alarm Grants permission to higher level
device to change alarm parameters of
the block
Local Grants permission to a local operator's
Operations panel or hand-held device to change
target mode, set point, or output of the
block, depending on block mode.
Program Turns off Program Operations
Operations permission grant.
Tune Turns off Tune permission grant.
Alarm Turns off Alarm permission grant.
Local Turns off Local Operations grant.
Operations
Honeywell
Description
R400
July 2010