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9.4.1.3
"Communication" tab
Purpose
The following communication settings can be made in this tab:
Field
Explanations/operating instructions
Cycle time
(default value: 1000
ms)
Updating of the values shown in the "Process value display" dialog box is carried
out in accordance with the time interval entered here.
Note: You can change the cycle time value for periodic communication jobs. We
recommend against significantly reducing the cycle time unless absolutely
necessary.
Identity
If the "Identity check" check box is selected, SIMATIC PDM performs an identity
check automatically each time there is any online communication.
Device diagnostics
If the "Diagnostics update" check box is selected, SIMATIC PDM performs
device diagnostics automatically each time there is any online communication.
HART
communication
If the "SHC mode enabled" option is activated, SIMATIC PDM independently
detects for the analog channels of HART remote I/Os whether the SHC function
(uninterrupted HART command sequence) as per the "HART on PROFIBUS"
specification from the "PROFIBUS & PROFINET International (PI)" fieldbus
organization is supported.
● SIMATIC PDM is able to use SHC mode if the HART module of the remote
I/O supports this mode.
This results in shorter reading and writing times for the parameter data of
HART field devices.
● If the HART module of the remote I/O does not support SHC mode, the
conventional communication method is used instead.
Note:
Communication with HART field devices interrupted:
If communication with individual HART field devices is interrupted repeatedly
when this option is used, you should deactivate it when working with the HART
field devices concerned.
Identity check and device diagnostics
Note
Reduction of times for servicing or loop check
You can reduce the load/read times by up to 20 seconds if you deactivate the identity check
and device diagnostics. You can still use the "Update diagnostics (Page 202)" function for
diagnostics.
During any communication with the field device, identity is checked and the diagnostics is
updated.
You have the option of disabling these functions
Manually updating the diagnostics is still possible
Menus and dialog boxes for SIMATIC PDM in the SIMATIC Manager
9.4 "Options" menu
Help for SIMATIC PDM (V8.2)
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Operating Manual, 02/2014, A5E33203676-AA