Redundant Power Inputs; Alarm Contact - Moxa Technologies EtherDevice User Manual

Redundant Power Inputs

MOXA EtherDevice Server has two DC power inputs located on its top panel. For detailed
instructions on how to connect the power wires to the terminal block connector, see the
Wiring the Redundant Power Inputs section from Chapter 3.
From the user's point of view, the function of the redundant power inputs is quite
straightforward. Both inputs can be connected simultaneously to live DC power sources. If
one power source fails, the other live source acts as a backup, and automatically supplies all
of MOXA EtherDevice Server's power needs.

Alarm Contact

MOXA EtherDevice Server has one Alarm Contact located on the top panel. For detailed
instructions on how to connect the Alarm Contact power wires to the 3-terminal terminal
block connector, see the Wiring the Alarm Contact section from Chapter 3.
The Alarm Contact has two terminals that form a Fault circuit for connecting to an alarm
system. These two contacts form a closed circuit when MOXA EtherDevice Server is
receiving power from both DC power inputs. The circuit opens if power to one of the
power inputs is cut off, or if the MOXA EtherDevice Server self-test fails, alerting the user
to check either the power supply or function of the Server.
A typical scenario would be to connect the Fault circuit to a warning light located in the
control room. The light can be set up to either switch on, or start blinking when a fault is
detected.
4-2 MOXA EtherDevice Server User's Manual