OPTICAL SYSTEMS DESIGN
DOC ID: 10115304
OSD2251P OPERATOR MANUAL
PAGE 12
2.2.5
ALARM CONNECTION
The OSD2251P has two monitoring alarm outputs: 1) Ring to Bus Alarm and 2) Temperature Alarm.
The alarm connections and conditions for alarm outputs are as set out in Table 3. There are four pins on
the 3.5mm terminal block used alarm output. Maximum ratings the OSD2251P relay can drive is
100mA @ 46V
(max)
. Note: Alarm output has no polarity.
TABLE 3: ALARM CONNECTIONS
Alarm
Output
Alarm1 Ring /Bus Status
Alarm CH2 Temperature
Open
Ring
Less than 90
°
C
Closed
Bus*
Higher than 90
°
C
*Note: Bus alarm is only triggered
after
a ring connection is established.
FIGURE 5: ALARM OUTPUTS
FIGURE 6: CONTACT CLOSURE OUTPUT
Alm1
Alm2
OSD2251P