Chapter 2 Overview
Front-Panel Description
2-16
Catalyst 2955 Hardware Installation Guide
78-14944-03
Alarm Relay LEDs
Two alarm relay LEDs labeled MAJ and MIN are to the right of the uplink port
status LEDs, as shown in Figure 2-7 and Figure 2-8. These LEDs reflect the state
of the major and minor system alarms.
You can use the Cisco IOS command-line interface (CLI) to configure the major
and minor LEDs to drive the relay contacts so that the connected external alarm
device state mirrors the alarm state of the major (MAJ) or minor (MIN) LED. You
can also use the CLI to associate port and global status alarms to one or both
relays. See the switch software configuration guide for details.
Warning
The switch relays are rated at 1 Amp and have a voltage limit of 30 VDC and 0.3
Amp at a voltage limit of 125 VAC. It is dangerous to exceed these limitations in
a hazardous environment.
An electrical arc can occur when you connect or disconnect the relay wires
with field side power applied. This could cause an explosion in switch
installations in a hazardous location. Before proceeding, be sure that power is
removed or the area is not hazardous.
Statement 1061
.
Table 2-6 lists the LED colors and meanings.
Note The minor LED is disabled by default.
Table 2-6 Alarm and Relay LEDs
LED Color Meaning
Major relay
(MAJ)
Off Environmental temperature is within normal range, or connected
alarm is not in a state of fault.
Red Environmental temperature exceeds maximum threshold, or
connected alarm is in a state of fault.
Minor relay
(MIN)
Off Connected alarm is not in a state of fault.
Red Connected alarm is in a state of fault.
