Field Bus Interface¶
| Interface socket | 5-pin COMBICON |
| Transmission standard | ISO 11898, potential-free |
| Transmission protocol | CANopen® (CAN), 1 Mbaud max. |
| Transfer rate (baud rate) | 20 kbit/s, 125 kbit/s, 250 kbit/s, 500 kbit/s and 1 Mbit/s |
The CANopen® connector has the following pin assignment:
Pin assignment of the CANopen® field bus interface, Combicon, 5-pole, male, Communication module interface
Pin assignment of the CANopen® field bus interface, Combicon, 5-pole, female, removable plug with spring terminals
| Pin No. | Signal | Meaning |
|---|---|---|
| 1 | CAN_GND | CAN reference potential |
| 2 | CAN_L | Bus line, receive/transmit line, LOW |
| 3 | CAN_SHLD | Shield of the bus line |
| 4 | CAN_H | Bus line, receive/transmit line, HIGH |
| 5 | Not connected | - |
Cable Lengths
The maximum possible cable length of a CANopenâ network depends on the baud rate (transmission rate).
| Bit Rate (speed) | Bus Length |
|---|---|
| 1 Mbit/s | 30 m |
| 800 kbit/s | 50 m |
| 500 kbit/s | 100 m |
| 250 kbit/s | 250 m |
| 125 kbit/s | 500 m |
| 62.5 kbit/s | 1000 m |
| 20 kbit/s | 2500 m |
| 10 kbit/s | 5000 m |
Types of Bus Cables
For CANopen®, only bus cables with characteristics as recommended in ISO 11898 have to be used. The requirements to the bus cables depend on the length of the bus segment. Regarding this, the following recommendations are given by ISO 11898:
| Length of segment [m] | Bus cable | Max. baud rate [kbit/s] | ||
|---|---|---|---|---|
Conductor cross section [mm²] |
Line resistance [Ω/km] |
Wave impedance [Ω] |
||
| 0…40 | 0.25…0.34 / AWG23, AWG22 | 70 | 120 | 1000 at 40 m |
| 40…300 | 0.34…0.60 / AWG22, AWG20 | < 60 | 120 | < 500 at 100 m |
| 300…600 | 0.50…0.60 / AWG20 | < 40 | 120 | < 100 at 500 m |
| 600…1000 | 0.75…0.80 / AWG18 | < 26 | 120 | < 50 at 1000 m |
Bus Terminating Resistors
The ends of the data lines have to be terminated with a 120W bus termination resistor. The bus termination resistor is usually installed directly at the bus connector.
CANopen® interface, bus terminating resistors connected to the line ends
| 1 | CAN_GND |
| 2 | CAN_L |
| 3 | Shield |
| 4 | CAN_H |
| 5 | Data line, twisted pair |
| 6 | COMBICON connection, CANopen® interface |
DeviceNet™interface, bus terminating resistors connected to the line ends
| 6 | DeviceNet™ power supply |
| 7 | COMBICON connection, DeviceNet™ interface |
| 8 | Data lines, twisted pair cables |
| 9 | red |
| 10 | black |
| 11 | white |
| 12 | blue |
| 13 | bare |
Note
The earthing of the shield should take place at the switch-gear cabinet, see System-Data AC500 System Data AC500.