Moxa EDS-P308-SS-SC [11/16] Eds p308 series s alarm contact

- 11 -

EDS-P308 Series’s Alarm Contact

The EDS-P308 Series has one alarm contact located on its top panel. For

detailed instructions on how to connect the alarm contact power wires to

the two middle contacts of the 6-contact terminal block connector, see

the Wiring the Alarm Contact section on page 10. 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 switch on when a fault is detected.

The alarm contact has two terminals that form a Fault circuit for

connecting to an alarm system. The two wires attached to the Fault

contacts form an open circuit when (1) EDS has lost power from one of

the DC power inputs, or (2) one of the ports for which the corresponding

PORT ALARM DIP Switch is set to ON is not properly connected.

If neither of these two conditions occurs, the Fault circuit will be closed.

EDS-P308 Series’s DIP Switch Settings

ON:

Enables the corresponding PORT Alarm. If

the port’s link fails, the relay will form an

pen circuit and the fault LED will light up.

Off:

Disables the corresponding PORT Alarm.

The relay will form a closed circuit and the

Fault LED will never light up.

Wiring the Alarm Contact

The alarm contact consists of the two middle contacts of the terminal

block on EDS’s top panel. Refer to below 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

contact terminal block connector are used to

detect both power faults and port faults. The

two wir

es attached to the Fault contacts form

an open circuit when:

1. EDS has lost power from one of the DC

power inputs.

2. One of the ports for which the

corresponding PORT ALARM DIP Switch is

set to ON is not properly connected.

If neither of these two

conditions is satisfied,

the Fault circuit will be closed.