Transition Networks SM24-1000SFP-AH, Installation Manual

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Connecting to the Alarm Port
3
Connecting to the Alarm Port
The DB-15 alarm port on the switch’s front panel is used to provide alarm, service
port, and BITS clock reference interfaces. The switch supports two sets of alarm
relay contacts (major and minor), and 4 external customer site alarm inputs. It also
provides an alarm cutoff button (labeled ACO). The pin assignments used to
connect to the alarm port are provided in the following table.
Figure 3-10 Alarm Port (D-15) Pin-Out
Wiring Map for Alarm Cable
The signals include relay contacts for major and minor system alarms, and external
alarm inputs.
Table 3-2 Alarm Cable Wiring
Switch’s Alarm Port Function
1 (MJR_ALARM_CNTR) Common contact for major alarm relay.
2 (MNR_ALARM_CNTR) Common contact for minor alarm relay.
3 (ALARM_IN3_EXT_P
*
)
* P indicates positive input.
External alarm input 3 (external relay dry contact closure to pin 13).
4 (ALARM_IN4_EXT_P) External alarm input 4 (external relay dry contact closure to pin 8).
5 (No Contact)
6 (MJR_ALARM_NO)
Normally open during major alarm state.
7 (MNR_ALARM_NO) Normally open during minor alarm state.
8 (ALARM_IN4_EXT_RTN
†
)
† RTN indicates return to Ground.
External alarm input 4 (external relay dry contact closure from pin 3).
9 (ALARM_IN1_EXT_P) External alarm input 1 (external relay dry contact closure to pin14).
10 (ALARM_IN2_EXT_P) External alarm input 2 (external relay dry contact closure to pin 15).
11 (MJR_ALARM_NC) Normally closed during major alarm state.
12 (MNR_ALARM_NC) Normally closed during minor alarm state.
13 (ALARM_IN3_EXT_RTN) External alarm input 3 (external relay dry contact closure from pin 3).
14 (ALARM_IN1_EXT_RTN) External alarm input 1 (external relay dry contact closure from pin 9).
15 (ALARM_IN2_EXT_RTN) External alarm input 2 (external relay dry contact closure from pin 10).
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