B&R MAPPC700A-ENG, Руководство пользователя

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Technical data • Individual components
Chap
ter 2
Te
chn
ica
l da
ta
211 Panel PC 700 with 945GME N270 CPU board User's Manual V 1.16
RS422 - Bus length and cable type
The RTS line must be switched on to activate the sender.
The maximum transfer rate of 115 kbit/s depends on the cable type being used.
The material used for the cable should preferably have all or most of the following properties in
order to reach an optimal transfer rate.
RS485 interface operation
The pins of the RS422 default interface (1, 4, 6 and 9) should be used for operation. The pins
should be connected as shown.
The RTS line must be switched each time the driver is sent and received, and there is also no
automatic switch back. This cannot be configured in Windows.
Distance [m] Transfer rate [kbit/s]
1200 Typ. 115
Table 88: RS422 - Bus length and transfer rate
RS422 cable Property
Signal lines
Cable cross section
Wire insulation
Conductor resistance
Stranding
Shielding 4 x 0.25 mm² (24AWG/19), tinned Cu wire
PE
≤
82
Ω
/ km
Wires stranded in pairs
Paired shield with aluminum foil
Grounding line
Cable cross section
Wire insulation
Conductor resistance 1 x 0.34 mm² (22AWG/19), tinned Cu wire
PE
≤
59
Ω
/ km
Outer sheathing
Material
Characteristics
Total shielding PUR mixture
Halogen free
From tinned cu wires
Table 89: RS422 - Cable requirements
Figure 114: Add-on RS232/422/485 interface - operated in RS485 mode
RXD
RXD
TXD
TXD
9
6
4
1
DATA
DATA