Westermo LRW-702-F2, Руководство пользователя

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Calculating System Delay
Data exchange between LONWORKS devices via a LRW-702-F2 fibre optic link will be
delayed due to the length of the optical fibre and the signal processing within the LRW-
702-F2 units. The following equation can be used to calculate the overall system delay:
Maximum delay (µs) = Total fibre distance (m) / 200 + Number of LRW-702-F2 units
For example, in a multidrop system comprising four LRW-702-F2 units connected
together using three 1,5 km fibre links, the end to end delay will be: 3 x 1500 / 200 + 4
= 26,5 µs
Reconfiguration Time under Faulty Condition
The reconfiguration time is determined by the time it takes to detect a faulty fibre
segment plus the time it takes to transport an error status message through to the
LRW-702-F2 focal point unit. The time to transport an error status message to the focal
point unit is dependent on how many units the error status message has to be repeated
through and the total fibre length delay. The following equation can be used to calculate
the reconfiguration time:
Reconfiguration time (µs) = Total fibre distance (m) / 200 + Number of LRW-702-F2
units + 3µs