Siemens SIMATIC PCS 7 FOUNDATION Fieldbus, Руководство по вводу в эксплуатацию

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Bus parameters Setting
range (de‐
fault)
Meaning and limiting values
Maximum Inactivity to
claim LAS Delay
1 - 4095
(100) Delay time (device-internal)
Time which an LAS-capable FF device needs from the detection of the failure of the
LAS until a request is sent for takeover of the LAS (ClaimLAS).
The minimum value for this parameter is determined by the maximum value of all
the LAS-capable FF devices in the FF segment.
LAS Database Distri‐
bution Period
100 - 55000
(5000) Time period for distribution of the LAS database (in milliseconds)
This time period covers the times for the following processes:
● Establishment of the connection to LAS-capable FF devices in the FF segment
● Distribution of the LAS database to FF devices in the FF segment
Recommendation: Set a value between 1000 and 5000.
Ap Clock Sync Interval 0..255
(10)
"Application Clock Synchronisation Interval" is a specific parameter for those devices
that can execute this time synchronization (date and time) on the FF segment. It is
not necessary that this device is LAS on the FF segment. Only one device may
actively perform time synchronization on the FF segment.
Set the parameter according to the specifications of the device manufacturer.
Start-up time 20 s Time period for start-up of all devices on the FF segment (in seconds)
Selection: 20 to 180 seconds (levels: every 20 seconds)
Stale Count Limit 0 - 255
(3) Maximum number of failed communication attempts
When the value is exceeded, the device in question terminates communication with
the FF segment.
0: Checking is turned off in the device.
5.3.3 How to assign bus parameters
Settings of the FOUNDATION Fieldbus are assigned in PCS 7 systems using HW Config or
NetPro.
The necessary bus parameters can be determined automatically or set individually. Set the
bus parameters using the "Properties - FOUNDATION Fieldbus" dialog box.
Meaning of the S7 subnet ID
The S7 subnet ID comprises two numbers separated by a hyphen:
● Number for the project
● Number for the subnet
If you want to go online with a PG/PC without a consistent project, you must know the S7
subnet ID. When you print the network configuration, the S7 subnet ID will also be printed.
Connecting a link master (LAS) to an active FF segment
Before you connect a field device or the bus link (FF Link or Compact FF Link), assign the bus
parameters in a separate action.
Example:
Engineering
5.3 Parameter assignment
FOUNDATION Fieldbus
Commissioning Manual, 02/2015, A5E32711026-AC
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