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PROFIBUS Optical Bus Terminal (OBT)
Operating Instructions, 04/2016, C79000-G8976-C122-07
29
Technical data
7
Table 7- 1
Technical specifications
General
Operating voltage (safety extra-low voltage, SELV or to NEC
Class 2)
24 V= (19.2 V to 28.8 V)
Current consumption at 24 V input
max. 180 mA
Bleed resistance between terminal M and terminal
11 Mohms
Transmission speed
12 Mbps, 6 Mbps, 3 Mbps, 1.5 Mbps, 500 Kbps, 187.5 Kbps
, 93.75 Kbps, 45.45 Kbps, 19.2 Kbps, 9.6 Kbps
Setting the transmission speed
performed automatically
Operating mode
optical bus
Bit error rate
<10
-9
Input channel 1 to 3
Bit length
jitter
0.7 to 1.3 tBit
-0.03 to +0.03 tBit
Output channel 1 to 3
Bit length
jitter
0.99 to 1.01 tBit
-0.003 to +0.003 tBit
Signal latency (any input/output)
≤
6 tBit
Cascading depth optical bus
limited only by latency
Electrical channel
Input/output signal
RS-485 level
Input dielectric strength
-7 V to +12 V
Minimum current at 5 V (for terminators)
10 mA
Electrical isolation to 24 V input
Isolation due to functionality, not safety!
Optical channel
Optical source
LED
Injectable optical power
– with plastic fiber 980/1000
– with PCF fiber 200/230
P
T(min)
P
T(max)
– 5.9 dBm
+0.5 dBm
– 16 dBm
-1.5 dBm
Sensitivity of receiver
– with plastic fiber 980/1000
– with PCF fiber 200/230
P
R(min)
P
R(max)
-20 dBm
0 dBm
-22 dBm
-2 dBm
Wavelength
640 nm to 660 nm