Korenix JetNet 3705, User Manual

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Hardware Installation
Korenix JetNet 3705 Series Industrial PoE Switch User’s Manual 2-5
3. OPTIONAL – DC IN: JetNet 3705 and JetNet 3705f Series Industrial Ethernet Switch has an
additional power jack for the connection of AC-DC power converters (wall-transformer type)
designed for office use. Be sure that the output voltage is at 48V DC to power the unit. Refer
to switch PWR LED to verify the power via the DC-IN jack.
Note : If all three power inputs are connected (DC IN, PWR 1, PWR 2), the JetNet will be
powered from the highest connected voltage. The unit will not alarm for loss of DC IN power, the
alarm function only applies to loss of power at PWR1 or PWR2.
Wiring the Relay Output
The alarm output relay contacts are located at the two middle terminals of the power terminal
block, between PWR2 and PWR1 as shown in the figure below. These contacts are single-pole
single-throw (SPST) and are energized (open-circuited) for normal operation. These contacts
will close if the unit is not powered, or if either DC power 1 or power 2 fails, or if a port connection
fails (if that port alarm DIP switch is ON). The figure below gives an example of how the output
alarm relay operates.
Note : The relay contacts are energized (open) for normal operation and will close for fault
conditions. This contact does not supply any power and is rated up to 24V DC at 1A current.
1. Connect to the SPST alarm relay terminals as per your application. Insert your load wires
and tighten the alarm terminal screws to prevent the wires from coming loose. These
contacts are open for normal operation and close in alarm. Do not exceed 24V and 1A
current.
2. Verify that your load is wired to the central two terminals of this terminal block. After the relay
is wired, insert this terminal block into its socket.