Pluto Bus Communication; Bus Cabling - ABB PLUTO Safety-PLC Operating Instructions Manual

9

Pluto bus communication

Up to 32 Pluto units can be interconnected with CAN-bus. Communication is achieved by
connecting a twisted pair cable to the CH and CL terminals. When this connection is made the
Pluto units can read each other's I/O.
When the bus is connected each Pluto unit executes its own individual program and operates
independently, however it can read other units I/O.
An interruption of the bus connection results in the I/O in the unit with which communication is
lost, being regarded as a "0" condition by other units on the bus. In this situation all units will
continue program execution with the consequences of the fault being dependent upon the
application program. For instance, if an emergency stop button connected to one unit is used
by another unit as a condition for setting an output, the output will switch off if communications
are lost. Outputs generated by I/O connected directly to a unit are not affected by interruption
of communications.
9.1

Bus cabling

The maximum length of CAN-bus cabling is dependent on the transmission speed. At the
default setting of 400 kbit/s the maximum total length is 150 meters. (This length can be
extended by the use of Gateways as bridges. See Pluto Gateway Manual chapter 1 "General"
and chapter 8 "CAN bridge mode"). At each end of the bus a termination resistor of 120 W must
be installed. When a Pluto unit is working alone and no bus-cable is connected, it must still be
equipped with a termination resistor.
The bus connection should be made with a twisted pair cable to the CH and CL terminals.
120 W
C H I1 I3 I6 IQ10 Q2
C L I0 I2 I4 I5 I7 IQ11 Q3
PLUTO
K
IQ 12 IQ14 IQ16 Q0 Q1
IQ13 IQ15 IQ17 ID 0V +24V
Connection of CAN bus: CH to CH and CL to CL.
A terminating resistor in each end of the bus. Stubs are restricted to certain max length and shall not
have terminating resistor.
C H I1 I3 I6 IQ10 Q2
C L I0 I2 I4 I5 I7 IQ11 Q 3
PLUTO
K
IQ12 IQ14 IQ16 Q0 Q1
IQ13 IQ15 IQ17 ID 0V +24V
C H I1 I3 I6 IQ10 Q2
C L I0 I2 I4 I5 I7 IQ11 Q3
PLUTO
K
IQ12 IQ14 IQ16 Q0 Q1
IQ13 IQ15 IQ17 ID 0V + 24V
C H I1 I3 I6 IQ10 Q2
I0 I2 I4 I5 I7 IQ 11
C L Q3
PLUTO
K
IQ12 IQ14 IQ16 Q0 Q1
IQ 13 IQ15 IQ17 ID 0V +24V
39
120 W
120 W
C H I1 I3 I6 IQ10 Q2 C H I1 I3 I6
C L I0 I2 I4 I5 I7 IQ11 Q3 C L I0 I2 I4 I5 I7
PLUTO PLUTO
K K
IQ12 IQ14 IQ16 Q0 Q1 IQ12 IQ14 IQ16 Q0
IQ13 IQ15 IQ 17 ID 0V +24V IQ13 IQ15 IQ17 ID
2TLC172001M0211_A
IQ10 Q2
IQ11 Q3
Q1
0V +24V