GE AF-600 FP BACnet Operating Instructions Manual page 12

3.1.2 Cabling
Cable lengths and number of nodes
The maximum cable length allowable in one segment is dependent on the transmission speed. The total cable length includes drop cables if any. A drop cable is
the connection from the main bus cable to each node if a T-connection is used instead of permissible cable length and maximum number of nodes/Drivess with
1, 2, 3 and 4 bus segments.
Drop cable connection (i.e. T-connection) beyond the cable lengths indicated is not recommended, due to the increased risk of reflection occurring. Instead, GE
recommends direct connection of the drive.
Note that a repeater is a node in both of the two segments it connects. The number of frequency converters is based on a single master system. If there are two
or more masters (e.g. PC tools, Routers), the number of frequency converters must be reduced correspondingly.
Network topology
Free topology without repeater
Free topology with one repeater
Free topology maximum device-to-device
Bus topology single terminated
Bus topology double terminated without repeater
Bus topology double terminated with one repeater
Bus topology maximum stub length
The length statements in the tables above are valid for bus cable with the following properties:
- Impedance: 135 to 165 Ohm at a measuring frequency from 3 to 20 MHz
- Resistance: <110 Ohm/km
- Capacitance: <30 pF/m
- Damping: max. 9 dB over the whole wire length
-
Cross section: max. 0.34 mm 2
- Cable type: twisted in pairs, 1 x 2, or 2 x 2, or 1 x 4 wires
- Screening: Copper-braided screen or braided screen and foil screen
Use of the same cable type throughout the entire segment is recommended to avoid impedance mismatch.
, corresponding to AWG 22
AF-600FP BACnet
Maximum cable length
500 m
1000 m
500 m
500 m
2700 m
5400 m
3 m
3
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