ifm
System Manual
ecomat
mobile
SmartController (CR2500) V05
CAN in the ecomatmobile controller
Physical connection of CAN
53
8.3.3
Bus cable length
The length of the bus cable depends on:
•
type of the bus cable (cable, connector),
•
cable
resistance,
•
required transmission rate (baud rate),
•
length of the spurs.
To simplify matters, the following dependence between bus length and baud rate can be assumed:
10
0
50
1000
10000
5
10
20
50
100
200
500
1000
Bus-Länge
Bus length
[m]
Baudrate
Baud rate
[kBit/s]
Figure: bus cable length
Baud rate [kBit/s]
Bus length [m]
Bit length nominal [µs]
1 000
30
1
800 50 1.25
500 100 2
250 250 4
125 500 8
62.5 1
000 20
20 2
500 50
10 5
000 100
Table: Dependencies bus length / baud rate / bit time
NOTE
These declarations apply to CAN layer 2.
Other CAN protocols (e.g. SAE J1939 or ISO 11992) have other requirements!
