Nesis III — Installation Manual
8.1
Connector and Plug
8.1
Connector and Plug
We are using standard Ethernet computer cable with RJ45 connector on each
side. Communication leads are central twisted pair leads – pins 4 and 5, while
other pins are used as a power supply for connected devices.
The cable can be bought in almost any computer shop. Although connector
seems a bit
cheap
it is very reliable. I do not remember any plug/connector
contact problem or failure in last 10 years.
A
A
A-A
1...8
1...8
8 … 1
Figure 22:
Designation of the CAN bus pins.
Pin
Description
1,2,3
+12V
4
CAN low
5
CAN high
6,7,8
GND – Ground
Table 4:
Description of the CAN bus pins.
Our CAN bus system is running at 500 kBit/s.
8.2
CAN Topology
CAN system can be used in different topologies. We are using line/bus type
topology. Figure 23 shows schematic of this topology. It consists of one main
CAN bus line and several devices (also referred to as nodes) are connected to
the main bus via short connections. The connecting lines shall be short – up
to 30 (50) cm, while the main line can be up to 40 meters long. Each side of
the main bus line must have a terminator, which is a 120 Ω resistor.
33
©
Kanardia
2018
