Juniper M120 - M120 Alarm Leds and Alarm Cutoff;Lamp Test Button; Table 3: M120 Alarm Leds and Alarm Cutoff;Lamp Test Button

Related
Documentation
M120 Control Board (CB) LEDs on page 48•
• Installing the M120 Craft Interface on page 185
• M120 Router Chassis Description on page 7
• Replacing the M120 Craft Interface on page 184
• M120 Craft Interface Description on page 11
• Maintaining the M120 Power Supplies on page 277
• Replacing Alarm Relay Wires on the M120 Craft Interface on page 183
• RJ-45 Connector Pinouts for the External Clock Ports on page 107
• RJ-45 Connector Pinouts for the M120 Routing Engine ETHERNET Port on page 106
• RJ-45 Connector Pinouts for the Routing Engine AUX and CONSOLE Ports on page 106
M120 Alarm LEDs and Alarm Cutoff/Lamp Test Button
Two large alarm LEDs are located at the upper left of the craft interface (see Figure 6
on page 11). The circular red LED lights to indicate a critical condition that can result in
a system shutdown. The triangular yellow LED lights to indicate a less severe condition
that requires monitoring or maintenance. Both LEDs can be lit simultaneously.
A condition that causes an LED to light also activates the corresponding alarm relay
contact on the craft interface, as described in “M120 Alarm Relay Contacts on the Craft
Interface” on page 17.
To deactivate red and yellow alarms, press the button labeled ACO/LT (for “alarm
cutoff/lamp test”), which is located to the right of the alarm LEDs. Deactivating an alarm
turns off both LEDs and deactivates the device attached to the corresponding alarm
relay contact on the craft interface.
Table 3 on page 13 describes the alarm LEDs and alarm cutoff button in more detail.
Table 3: M120 Alarm LEDs and Alarm Cutoff/Lamp Test Button
DescriptionStateColorShape
Critical alarm LED—Indicates a critical condition that
can cause the router to stop functioning. Possible
causes include component removal, failure, or
overheating.
On steadilyRed
Warning alarm LED—Indicates a serious but nonfatal
error condition, such as a maintenance alert or a
significant increase in component temperature.
On steadilyYellow
Alarm cutoff/lamp test button—Deactivates red and
yellow alarms. Causes all LEDs on the craft interface
to light (for testing purposes), when pressed and
held.
——
13Copyright © 2018, Juniper Networks, Inc.
Chapter 3: Chassis Components and Descriptions