Specifications

FOM-E3/ETH, FOM-T3/ETH Ver. 1.0 Alarm Relay 4-1
Chapter 4
Diagnostics and
Troubleshooting
4.1 Alarm Relay
FOM-E3/ETH and FOM-T3/ETH include a dry contact alarm relay port supported via
9-pin connector for major and minor alarms.
• Major alarms are initiated bit error rate at the fiber optic interface is 10
-6
or
worse.
• Minor alarms occur when an Alarm Indication Signal is received at the fiber
optic interface.
The dry contact port operates as Normally Open or Normally Closed, using
different pins of the alarm relay port connector (see
Figure 4-1 ).
Alarm Connector
Minor-NO
1
2
6
4
5
9
Major-NO
Major Alarm Relay
Minor Alarm Relay
Minor-NC
Major-NC
Minor-COM
Major-COM
Figure 4-1. Alarm Relay Connector Pinout
The relay positions are shown in the non-energized state (alarm active).
Note