ZyXEL Communications ES-3124 - Manual (Page 41)

Chapter 3 Hardware Overview
ES-3124 Series User’s Guide
41
3.3.2 DC Power Connection
"
This is only for the DC model of the Switch.
The Switch uses a single terminal block plug with four pins which allows you to connect up to
two separate power supplies. If one power supply fails the system can operate on the
remaining power supply. Use two wires to connect to a single terminal pair, one wire for the
positive terminal and one wire for the negative terminal. Make sure that no objects obstruct the
airflow of the fans.
"
The current rating of the power wires must be greater than 20 Amps. The
power supply to which the Switch connects must have a built-in circuit breaker
or switch to toggle the power.
Figure 19 Terminal Block Pairs
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When installing the power wire, push it wire firmly into the terminal as deep as
possible and make sure that no exposed (bare) wire can be seen or touched.
1
An exposed wire from a DC power source is dangerous. Use extreme care
when connecting a DC power source to the device.
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.
Teminal
Pair 1
Teminal
Pair 2