CHAPTER 3: INSTALLATION
ALARM CONTACTS FOR MONITORING INTERNAL POWER, AND SOFTWARE TRAPS
MULTILINK ML810 MANAGED EDGE SWITCH – INSTRUCTION MANUAL
3–11
3.5
Alarm Contacts for monitoring internal power, and
Software Traps
The Alarm Contacts feature, standard on Multilink ML810’s, provides two Form C Normally
Closed (NC) contacts to which the user can attach two sets of status monitoring wires at
the green terminal block.
The first NC Alarm Contact is a “Software Alarm” (labeled S/W), operated by user settings in
the MultiLink ML810 Managed Edge Switch firmware. The user can disable the Software
Alarm feature with a software configuration command if desired. When the Software
Alarm is enabled, the Form C Normally Closed (NC) contact is held close during normal
software operation. A user-defined software malfunction, such as an SNMP Trap or a
Software Security violation or an S-Ring Fault, causes the contact to open and thus
triggers an alarm in the user’s monitoring system
The second NC Alarm Contact is held closed when there is power on the main board inside
of the Switch. This provides a “Hardware Alarm” (labeled H/W) because the NC contacts will
open when internal power is lost, either from an external power down condition or by the
failure of the power supply inside of the Switch.
Useful info. about Alarm contacts:
1.
There are four terminal blocks (1,2,3,4) provided next to the Console port.
2.
The left two pins (1,2) are hardware operated
3.
The right two pins (3,4) are software operated
4.
These are both NC (normally closed) relays
5.
The switch’s software operation needs to be enabled and set to get the Alarm
traps.
The Alarm Contacts are on the front left area (next to the Console port) of the Multilink
ML810 unit and are green in color as shown in the picture.
Figure 3-4: Alarm Contacts:
NOTE
Note
1 and 2 are hardware operated.
3 and 4 are software operated.
