Detcon DA-1 - Manual (Page 3)

Device # 485 Address
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 A
11 B
12 C
13 D
14 E
15 F
16 10
17 11
18 12
19 13
20 14
21 15
22 16
23 17
24 18
25 19
26 1A
27 1B
28 1C
... ...
... ...
255 FF
3.0 Alarm Status per Channel
The alarm status is constantly monitored by the on-board circuitry. Digital inputs will be monitored for
either open or closed contacts and analog inputs for set point violations or under/over range. The input
setup information such as NO/NC for digital inputs, analog set points and under/over range information is
software configurable.
In addition, a NO/NC common alarm relay is available in the DA-1 if needed (see wiring diagram). This will
be energized (de-energized) in the event of an alarm condition on any of the digital inputs.
4.0 Diagnostics
The diagnostics available on the module consist of the device health and open contact (digital inputs only)
supervision. Both the device health and the open contact supervision are provided as a 10XXX register.
If the open contact supervision is provided, the customer is responsible for installing the required end-of-line
resistor. A small current is passed through the resistor to create a voltage drop that is monitored by the DA-1.
Should this voltage drop go to zero, a bit will be set for that DA-1 channel denoting the open circuit condi-
tion.
Detcon Model DA-1 PG.3