InteliLite4 AMF20 Global Guide
54
The maximum length of the CAN bus depends on the communication speed. For a speed of 250 kbps,
which is used on the CAN1 bus (extension modules, ECU), the maximum length is 200 m.
The bus must be wired in linear form with termination resistors at both ends. No nodes are allowed except
on the controller terminals.
Shielded cable
1
must be used, and shielding must be connected to the terminal T01 (Grounding).
External units can be connected on the CAN bus line in any order, but keeping line arrangement (no tails,
no star) is necessary.
The CAN bus must be terminated by 120Ω resistors at both ends using a cable with following parameters:
Cable type
Shielded twisted pair
Impedance
120 Ω
Propagation velocity
≥ 75 % (delay ≤ 4.4 ns/m)
Wire crosscut
≥ 0.25 mm
2
Attenuation (@1MHz)
≤ 2 dB / 100 m
Note:
Communication circuits shall be connected to communication circuits of Listed equipment.
Note:
A termination resistor at the CAN (120 Ω) is already implemented on the PCB. For connecting, close
the jumper near the appropriate CAN terminal.
Image 4.50 CAN bus topology
1
Recommended data cables: BELDEN (
) - for shorter distances: 3105A Paired - EIA
Industrial RS-485 PLTC/CM (1x2 conductors); for longer distances: 3106A Paired - EIA Industrial RS-485
PLTC/CM (1x2+1 conductors)