INVT Goodrive350 Series, Operation Manual

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Communication extension card PROFIBUS communication card
-5-
3. Transmission rates and maximum transmission distances
The maximum length of a cable depends on the transmission rate. Table 2-2 describes
the transmission rates and corresponding transmission distances.
Table 2-2 Transmission rates and corresponding transmission distances
Transmission rate (kbps) A-type wire (m) B-type 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 -----
Table 2-3 Transmission wire parameters
Parameter A-type wire B-type wire
Impedance (Ω) 135–165 100–130
Capacitance of a unit length (pF/m) < 30 < 60
Circuit resistance (Ω/km) 110 --------
Wire core diameter (mm) 0.64 > 0.53
Sectional area of wire core (mm
2
) > 0.34 > 0.22
Besides the shielded twisted-pair copper cables, you can also use optical fibers for
transmission in a PROFIBUS system. When a PROFIBUS system is applied in an
environment with strong electromagnetic interference, you can use optical fiber conductors to
increase the high-speed transmission distance. Two types of optical fiber conductors can be
used. One is low-cost plastic fiber conductors that can be used when the transmission
distance is shorter than 50 m; and the other is glass fiber conductors that can be used when
the transmission distance is shorter than 1 km.
4. PROFIBUS bus connection diagram
PROFIBUS
master station
INVT inverter INVT inverter
A B B GND SHLD SHLD A B
CH-PA01 adapter
A
CH-PA01 adapter
Figure 2-3 PROFIBUS bus connection