User Manual

38
Fire & Security Products
Siemens Building Technologies
03.2003
10.9 Status request control
Status requests are not issues if incoming traffic is above a threshold level. This is par-
ticularly useful when LMS has to connect to large loops where the traffic should stay
below a critical level. The parameters below are used for:
set a delay between status requests with a random factor that can differentiate the vari-
ous station on the loop
set the traffic threshold level, in messages per sec.
set an additional wait, in sec., after the traffic level gets below the threshold so as to let
the random effect apply and prevent collisions
Field Values Meaning Notes
Request traffic
§ Minimum time …
§ Max.Random Time
§ Granularity
§ Time period …
§ Threshold …
§ Wait time …
§ Numeric, sec.
§ Numeric, sec.
§ Numeric
§ Numeric, sec.
§ Numeric, mesg
§ Numeric, sec.
Delay =
MinTime+RndTime*Granularity+Wait
Threshold is calculated as messages
per sec. within the given time period
Further delay after threshold is
reached and then traffic gets below it
again
Min. time between two
status requests
Default=30+10*0=30
Fast mode= 3+10*0=3