Emerson 3051S manual Device Capabilities Link Active Scheduler, Network Parameter Value

Rosemount 3051S

Reference Manual

00809-0200-4801, Rev BA April 2007

DEVICE CAPABILITIES Link Active Scheduler

Capabilities

The Rosemount 3051S can be designated to act as the backup Link Active Scheduler (LAS) in the event that the LAS is disconnected from the segment. As the backup LAS, the 3051S will take over the management of communications until the host is restored.

The host system may provide a configuration tool specifically designed to designate a particular device as a backup LAS. Otherwise, this can be configured manually as follows:

1. Access the Management Information Bose (MIB) for the 3051S.

2.To activate the LAS capability, write 0x02 to the

BOOT_OPERAT_FUNCTIONAL_CLASS object (Index 605). To deactivate, write 0x01.

Restart the processor.

Virtual Communication Relationship (VCRs)

There are a total of 20 VCRs. One is permanent and 19 are fully configurable by the host system. Twenty-five link objects are available.

Network Parameter	Value
Slot Time	6
Maximum Response Delay	4
Maximum Inactivity to Claim LAS Delay	47
Minimum Inter DLPDU Delay	7
Time Sync class	4 (1ms)
Maximum Scheduling Overhead	21
Per CLPDU PhL Overhead	4
Maximum Inter-channel Signal Skew	0
Required Number of Post-transmission-gab-ext Units	0
Required Number of Preamble-extension Units	1

Host timer recommendations

T1 = 96000

T2 = 1920000

T3 = 480000

Block Execution times

Analog Input = 20 ms PID = 25 ms Arithmetic = 20 ms Input Selection = 20 ms Signal Characterizer = 20 ms Integrator = 20 ms

Analog Output = 20 ms Output Splitter = 20 ms Multiple Analog Input = 20 ms Control Selector = 20 ms

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