Rockwell Automation 1606-XLP XM Electronic Overspeed Detection System - Manual (Page 33)

Publication GMSI10-UM015B-EN-E - June 2011
Installing the XM Electronic Overspeed Detection System 33
Wiring the XM-442 Relays
There are four normally energized (failsafe) relays in the XM-442 module.
Three relays serve as the shutdown relays. The fourth relay is the alarm relay.
The shutdown relays will be activated by any of the following conditions:
• Overspeed condition on any two (or all three) of the three XM-220
channels.
• Failure of a sensor, power supply, or logic device in any two (or all three)
of the three XM-220 channels (circuit fault).
The alarm relay will be activated by any of the following conditions:
• Overspeed condition on any one of the three XM-220 channels.
• Failure of a sensor, power supply, or logic device in any one of the three
XM-220 channels, or within the XM-442 module itself.
• Failure of the XM EODS primary or secondary power supply.
The appropriate relay(s) will activate within 40 milliseconds of the onset of any
of the above conditions.
Table 2.1 shows the on-board relay connections for the XM-442.
Figures 2.11 and 2.12 illustrate the behavior of the NC and NO terminals
when the relay is wired for either failsafe, nonalarm condition or failsafe, alarm
condition.
Table 2.1 Relay Connections for XM-442
Failsafe Operation
Shutdown Relay 1
Terminals
Shutdown Relay 2
Terminals
Shutdown Relay 3
Terminals
Alarm Relay
Terminals
Nonalarm
(Fig. 2.11 or
Fig. 2.13) Alarm
(Fig. 2.12 or
Fig. 2.14)
Wire Contacts Contact 1 Contact 2 Contact 1 Contact 2 Contact 1 Contact 2 Contact 1 Contact 2
Closed Opened COM 21 20 24 22 27 25 29 28
NO 5 4 8 6 11 9 13 12
Opened Closed COM 21 20 24 22 27 25 29 28
NC 39 38 42 40 45 43 47 46