2.1.5 Cable Routing
The PROFIBUS communication cable must be kept away from motor and brake resistor cables to avoid coupling of high frequency noise from one cable to the
other. Normally a distance of 8 in [200 mm] is sufficient, but maintaining the greatest possible distance between cables is generally recommended, especially
where cables run in parallel over long distances.
If the PROFIBUS cable must cross a motor cable or brake resistor cable, the cables must cross at an angle of 90°.
2.1.6 Connecting the Network
Proper termination of the network is essential. A mismatch of impedance
may result in reflections on the line that will corrupt data transmission.
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The Profibus DP Communications Module has a suitable termina-
tion, activated by switch 1 located on the Profibus option. The
switches must be on to terminate the network. The factory setting
is off.
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Nodes at the physical ends of each segment must be terminated.
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When power to the Profibus DP Communications Module is down,
please note that the termination is still active, although not func-
tional.
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Most masters and repeaters are equipped with their own termi-
nation.
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If an external termination circuit consisting of three resistors is
connected to the network, a 5 V DC power supply must be used.
Terminal 66 and 67 can be used for this.
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The CS pin on the Profibus connector is Control Select. When op-
tion goes into active state and sends a message, the CS pin goes
high (+5 Volts). This can be used to control optical transmitters etc.
or for triggering measurement equipment like an oscilloscope.
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D-sub 9 connector.
If desired, a D-sub 9 adaptor can be added as an option.
Note: If the D-sub 9 adaptor is used, please be aware that the ter-
mination switch on the Profibus option is set to OFF, to avoid dou-
ble termination, as the Profibus D-sub 9 connector also features a
termination switch.
62 = RxD/TxD-P red cable (Siemens B)
63 = RxD/TxD-N green cable (Siemens A)
66 and 67 are for use with external terminator resistor only
AF-650 GP/AF-600 FP Profibus DP Instruction Manual
DET-624
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