Technical data
Panel PC 2100 user's manual V1.17
169
CAN driver settings
The baud rate can be set either with predefined values or the bit timing register. For additional information, see
Automation Help.
Bit timing register 1
Bit timing register 0
Baud rate
00h
14h
1000 kbit/s
80h or 00h
1Ch
500 kbit/s
81h or 01h
1Ch
250 kbit/s
83h or 03h
1Ch
125 kbit/s
84h or 04h
1Ch
100 kbit/s
89h or 09h
1Ch
50 kbit/s
Table 137: CAN driver settings
CAN - Bus length and cable type
The type of cable to be used depends largely on the required bus length and number of nodes. The bus length is
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%:
Extension
Transfer rate
≤1000 m
Typ. 50 kbit/s
≤200 m
Typ. 250 kbit/s
≤100 m
Typ. 500 kbit/s
<20 m
1)
Typ. 1 Mbit/s
Table 138: CAN - Bus length and transfer rate
1)
The specified cable length is only valid with the values specified in
Tab. 137 "CAN driver settings"
. Cable lengths additionally depend on the values in the
timing register.
The material used for the cable should have all of the following properties or deviate from them as little as possible
to achieve an optimal transfer rate.
CAN cable
Property
Signal lines
Cable cross section
Wire insulation
Conductor resistance
Stranding
Shield
2x 0.25 mm² (24 AWG / 19), tinned copper stranded wire
PE
≤82 Ω/km
Wires stranded in pairs
Paired shield with aluminum foil
Ground line
Cable cross section
Wire insulation
Conductor resistance
1x 0.34 mm² (22 AWG / 19), tinned copper stranded wire
PE
≤59 Ω/km
Outer jacket
Material
Properties
Complete shielding
PUR compound
Halogen-free
Composed of tinned copper wires
Table 139: CAN cable requirements
Terminating resistor
A terminating resistor is integrated in the interface option above the ETH1 interface. A switch is used to enable
or disable the terminating resistor for the CAN bus interface. The L1 LED status indicator indicates whether the
terminating resistor is switched on or off.
Terminating resistor
On
The terminating resistor is switched on.
Off
The terminating resistor is switched off.
Terminating resistor
On
Off
Table 140: Terminating resistor
2.3.5.2.3.5 Shielding
For the interfaces on the 10-pin female connector, the interface shield can be put on pin 2 of the female connector.
