MP Filtri ICM, User Manual

Page: 42 / 82

42 Electrical Interface
Item Minimum Maximum
Voltage 9V DC 36V DC
Current 200mA
14.3 Machine Connector - Serial Interface
An RS485 or CANbus interface can optionally be connected to pins 1 and 3 (yellow
and green). This can be a PLC running customer software, or a PC with a RS485
adaptor running the supplied LPA-View software. To provide a reference the RS485
0V connection should also be linked to the ICM 0V (as shown on the drawing).
The standard ICM control protocol is Modbus RTU. Modbus is a freely available
open standard for industrial control. Adapters are available to interface to other in-
dustrial control busses. The standard LPA-View software from MP Filtri UK itself
uses Modbus to communicate with the ICM, but it is also possible for customers
to implement their own controllers – see chapter 18.
The CANbus protocol can also be used, see separate ICM-CANbus manual.
Figure 14.2 PC Control Example
Figure 14.2 shows a single ICM linked to a PC, using a USB-RS485 adaptor. 100
Ohm termination resistors should be fitted as shown for long cables, for example
over 10m. Twisted pair wiring should be used for any length over 2m.
Figure 14.3 shows how to connect two or more ICM devices to a multi-drop RS485
network. Any termination resistors should be fitted to the network cable ends only.
Spurs off the main RS485 bus should be kept as short as possible, e.g. below 2m.
Normally the pre-wired 3m cable available for the ICM would be used, with a