Technical data

LED Indicators

14-Slot Shelf

Chapter 2

Alarm Display Panel Telco Alarms

The following section describes some of the alarm interfaces, LEDs, and other functions.

Telco Alarm Interface

The ADP provides a Telco Alarm interface on the DB15-male connector. The Telco Alarm interface relay

circuits are capable of carrying 60 VDC or 1 A with a max. rating of 30 VA. The ADP accepts timed pulse

inputs for clearing Minor and Major alarm states.

NOTE There is no test for the Critical state.

Reset is accomplished by asserting a voltage differential from 3.3 V to 48 V for between 200 and 300 ms. The

acceptance voltage range is from 0 to 48 VDC continuous (handles up to 60 VDC at a 50% duty cycle). The

current drawn by a reset input does not exceed 12 mA.

Telco Alarm LEDs

The Shelf Alarm Display provides the Telco Alarm LEDs. These LEDs indicate presence of Critical, Major

and Minor alarms as follows:

Telco Alarm Cutoff Pushbuttons

The Telco Alarm Cutoff push button (RST) on the Shelf Alarm Display activates the Alarm Cutoff (ACO)

state. When ACO is activated, the active Alarm LEDs blink and all of the alarm relays are deactivated.

22 RST_PB Signal from Alarm Cutoff Push Button

23 LED_FT-FAIL_1 Signal to Fan Tray Left Alarm LED

24 LED_FT_FAIL_2 Signal to Fan Tray Center Alarm LED

25 LED_FT_FAIL_3 Signal to Fan Tray Right Alarm LED

26 LED_FT_OK_1 Signal to Fan Tray Left OK LED

27 LED_FT_OK_2 Signal to Fan Tray Center OK LED

28 LED_FT_OK_3 Signal to Fan Tray Left OK LED

Table 2-6 Telco Alarm LEDs

State Description

Off No alarm triggered

On Alarm triggered

Blinking Alarm Cutoff (ACO) is activated

Table 2-5 Alarm Display Panel Horizontal Board Pin Assignment (Continued)

Pin Signal Name Description