3.2.4 PROFIBUS connector and cables
PROFIBUS插头和线缆
Fieldbus interface 现场总线接口
The PROFIBUS DP connector features the following pin assignment:
PROFIBUS DP插头针脚定义如下：
Bus link总线连接
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Type
类型
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Twisted pair wire (shielded)
屏蔽双绞线
|
|
Impedance level
阻抗大小
|
135…165 Ω
|
|
Cable capacity
电缆容量
|
< 30 pF/m
|
|
Cable core diameter
单芯电缆直径
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≥ 0.64 mm
|
|
Cable core cross-section
单芯截面积
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≥ 0.34 mm2
|
|
Resistance per cable core
单芯电阻
|
< 55 Ω/km
|
|
Loop resistance (resistance of two cable cores)
回路电阻（两芯电阻）
|
< 110 Ω/km
|
电缆长度
The maximum cable length of a PROFIBUS subnet within one segment depends on the baud rate (transmission rate).
|
Transmission rate in kBit/s
传输速率
|
Maximum cable length
最大线缆长度
|
|
9.6;19.2; 45.45; 93.75
|
1200m |
|
187.5
|
1000 |
|
500
|
400 m
|
|
1500
|
200 m
|
|
3000, 6000, 12000
|
100 m
|
Bus termination
总线终端
Both bus segment ends must be provided with a termination resistor. These resistors are usually integrated into the PROFIBUS connector. As the bus termination is active, it must be ensured that both terminations are supplied with +5 V by a module or an external power supply.
所有的总线末端都需要由终端电阻。这些电阻器通常集成到 PROFIBUS 连接器中。由于总线总是活跃的，因此必须确保两个端接端都由模块或外部电源提供 +5 V。