Chapter 3 Hardware Overview
MGS3520 Series User’s Guide
31
To connect a power supply:
1
Use a screwdriver to loosen the terminal block captive screws.
2
Connect one end of a power wire to the Switch’s
RTN
(return) pin and tighten the captive screw.
3
Connect the other end of the power wire to the positive terminal on the power supply.
4
Connect one end of a power wire to the Switch’s
-48V
(input) pin and tighten the captive screw.
5
Connect the other end of the power wire to the negative terminal on the power supply.
6
Insert the terminal block plug in the Switch’s terminal block header.
3.1.5 Signal Slot
The
Signal
slot (fitted with the signal connector) allows you to connect devices to the Switch, such
as sensors or other ZyXEL switches which support the external alarm feature. This feature is in
addition to the system alarm, which detects abnormal temperatures, and voltage levels on the
Switch.
Your Switch can respond to an external signal in four ways.
• The
ALM
LED shows an alert.
• The
Signal
slot can send an external alarm on to another device. By daisy-chaining the signal
sensor cables from one Switch to another ZyXEL switch which supports this feature, the external
alarm alert (but not the system alarm) is received on each Switch.
• The Switch can be configured to send an SNMP trap to the SNMP server. See
for more information on using SNMP.
• The Switch can be configured to create an error log of the alarm. See
for more information on using the system log.
3.1.5.1 Connect a Sensor to the Signal Slot
This section shows you how to connect an external sensor device to the Switch.
1
Use a connector to connect wires of the correct gauge (18 AWG or larger) to the sensor’s signal
output pins. Check the sensor’s documentation to identify its two signal output pins.
2
Connect these two wires to any one of the following pairs of signal input pins on the Switch’s
Signal
connector--(4,5) (6,7) (8,9) (10,11). The pin numbers run from the right side of the connector to
the left.
2a
Connect each of the sensor’s two signal output wires to the
Signal
connector by depressing
the spring clip corresponding to the pin you are connecting to.
2b
Insert the wire and release the spring clip.
2c
Repeat the process for the sensor’s other signal output wire. A total of four sensors may be
connected to the
Signal
connector in this way using the remaining signal input pins.
3
Insert the alarm connector into the
Signal
slot.