INVT GD300-015G-4 - Page 239

Goodrive300 Series VFD Extension card
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Terminal
A.2.6.4 Transmission rate and maximum distance
Maximum length of cable depends on the transmission rate. The Table below shows the relationship
between transmission rate and distance.
Transmission rate (kbps)
A-wire (m)
B-wire (m)
9.6
1200
1200
19.2
1200
1200
93.75
1200
1200
187.5
1000
600
500
400
200
1500
200
-----
12000
100
-----
Transmission line parameters:
Transmission rate (kbps)
A-wire (m)
B-wire (m)
Impedance (Ω)
135–165
100–130
Capacitance per unit length(pF/m)
< 30
< 60
Loop Resistance (Ω/km)
110
--------
Core wire diameter (mm)
0.64
> 0.53
Line-core cross-section (mm
2
)
> 0.34
> 0.22
Besides shielding twisted-pair copper wires, PROFIBUS can also use optical fiber for transmission in
an electromagnetic interference environment to increase the high-speed transmission distance there
are two kinds of fiber optical conductors, one is low-cost plastic fiber conductor, used distance is less
than 50 meters, the other is glass fiber conductor, and used distance is less than 1 kM.