B&R MAPPC700A-ENG, User Manual

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Technical data • Individual components
Chap
ter 2
Te
chn
ica
l da
ta
207 Panel PC 700 with 945GME N270 CPU board User's Manual V 1.16
Bus length and cable type
The type of cable used depends largely on the required bus length and the number of nodes.
The bus length is mainly determined by the bit rate. In accordance with CiA (CAN in Automation)
the maximum bus length is 1000 meters.
The following bus lengths are permitted with a maximum oscillator tolerance of 0.121%:
The material used for the cable should preferably have all or most of the following properties in
order to reach an optimal transfer rate.
Distance [m] Transfer rate [kbit/s]
≤
1000 Typ. 50
≤
200 Typ. 250
≤
60 Typ. 500
Table 81: Bus length and transfer rate - CAN
CAN cable Property
Signal lines
Cable cross section
Wire insulation
Conductor resistance
Stranding
Shielding 2 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 82: CAN cable requirements