User Manual

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Wiring the Alarm Contact
The alarm contact consists of the two middle contacts of the terminal
block on the switch’s top panel. You may refer to the next section for
detailed instructions on how to connect the wires to the terminal block
connector, and how to attach the terminal block connector to the terminal
block receptor.
In this section, we explain the meaning of the two contacts used to
connect the alarm contact.
FAULT: The two middle contacts of the
6
-contact terminal block connector
are used to
detect both power faults and port faults. The
two wires attached to the Fault contacts form
a
n open circuit when:
1. The switch has lost power from
one of the
DC power inputs.
OR
2. The PORT ALARM DIP switch for one of
the ports is set to ON, but
the port is not
connected properly.
If
neither of these two conditions is satisfied,
the Fault circuit will
be closed.
Wiring the Redundant Power Inputs
The top two contacts and the bottom two contacts of the 6-contact
terminal block connector on the switch’s top panel are used for DC inputs.
Top and front views of one of the terminal block connectors are shown
here.
STEP 1: Insert the negative/positive DC
wires into the
V-/V+ terminals.
STEP 2:
To keep the DC wires from pulling
loose, use a small flat
-
blade screwdriver to
tighten the wire
-
clamp screws on the front
of the terminal block connector.
STEP 3:
Insert the plastic terminal block
connector prongs into the terminal block
receptor, which is
located on switch’s top
panel.
ATTENTION
Before connecting
the switch
to the DC power inputs, make sure
the DC power source voltage is stable.
You should also pay attention to the following:
• The terminal block plug must be suitable for 28-12 AWG (0.0804 to
3.31 mm
2
) wiring; use a torque value of 4.5 lb-in.
• Conductors suitable for use in an ambient temperature of 84°C must
be used for the power input terminal block.
• Only use one individual conductor at each clamping point.