Emerson Mentor MP Short Manual page 61

4.9.1 Serial communications connections
The Mentor MP has a serial communications port (serial port) as standard supporting
two wire EIA(RS)-485 communications.
Figure 4-9 Serial communications port
Table 4-22 RJ45 connections
The communications port applies a two-unit load to the communications network.
Connectors 2, 3, 7 and shield must always be made to the serial communications port.
Shielded cable must be used at all times.
In order to meet the requirements for SELV in IEC 60950 (IT equipment) it is
necessary for the control computer to be grounded. Alternatively, when a lap-top or
similar device is used which has no provision for grounding, an isolation device must
WARNING be incorporated in the communications lead.
Mentor MP Short Form Guide
Issue Number: 5
Pin
1
2
3
4
5
6
7
8
Shell
www.controltechniques.com
1
8
Function
120 Ω Termination resistor
RX TX
0V isolated
+24V (100 mA)
0V isolated
TX enable
RX\ TX\
RX\ TX\ (if termination resistors are
required, link to pin 1)
0V isolated
61