XtendLan DVR-475EL, User Manual

Page: 28 / 135

28
Figure 3-6

ALARMS1 in 1 to ALARM1 in 4 are corresponding to ALARM1 to ALARM4
respectively. The alarm gets activated in low voltage.

In ALARM1, 1-NO is normal open activation output. In ALARM2, 2-NO C
NC is a group of normal open/normal close activation output.

+12V is external alarm input. System needs external device to provide
+12V power and you can connect it to the alarm device power below 1A.

A/B is A cable and B cable to control 485 device. You can connect them to
devices such as decoder. Please parallel connect a 120
Ω
resistance if
there are too much PTZ decoders.

“ ”
：
Ground cable.
You can refer to the following sheet and Figure 3-7 for MB(D)/AL series alarm
input and output information.
Figure 3-7
Parameter
Grounding Alarm
Ground Ground line
Alarm in 1
…
4 1, 2,
…
, 4. Become activated in low voltage,
Relay Output 1,2,3,4: NO and C(Normally Open and Com)
5: NO,C and NC(Normally Open, Com, Normally Closed)
Terminal
Screw