Westermo ODW-622, Руководство пользователя

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14 6650-2233
Example
• Redundant ring, one data exchange between master and one slave.
One a master and 11 slaves with data rate 9600 bit/s dependent mode. 12 ODW-622 units
with a total fibre length of 40 km. A data exchange between master and one slave.
1. Fibre: The total optical fibre ring length delay.
40 x 5 μs = 200 μs
2. Optical repeaters:
The optical repeater delay x Number of optical repeaters
(excluded the two units connected to PLC master and slave).
10 x 3.0 μs = 30 μs
3. Converter electrical to fibre:
Signal processing delay x 2
(ODW-622 units connected to a master and addressed slave).
(1 t
bit
+ 0.6 μs) x 2 = (105 μs + 0.6 μs) x2 = 211 μs
4. Converter fibre to electrical:
Signal processing delay x 2
(units connected to PLC master and slave).
0.6 μs x 2 = 1.2 μs
5. The system delay is calculated by summing the delays in item 1 to 4 above:
200 μs + 30 μs + 211 μs + 1.2 μs = 442 μs