Pelco NET5308T-EXP manual Connecting Alarms, Supervised Alarms

LOAD:

EXTERNAL LIGHT/SIREN FUSE

NOC

POWER

MAX: 30 VDC, 2 A 125 VAC, 0.5 A

A5 A6 A7 A8

NO

C

NC

NO

C

NC

100-200 VAC - 50/60 HZ

0.7 AMP

Figure 17. Connecting a Relay Device

CONNECTING ALARMS

The NET5308T-EXP offers eight alarm inputs for external signaling devices, such as door contacts or motion detectors. Each alarm input can be either normally open or normally closed, either supervised or unsupervised.

Once configured, an alarm input can invoke many different activities, including triggering a relay device, sending an alert to a security office, changing the video recording settings, and storing pre-alarm video to an NVR5100 Series network video recorder or other Endura video recorder. You can connect switches or contacts directly to the unit without a separate power supply.

SUPERVISED ALARMS

When an alarm is configured as a supervised alarm, the NET5308T-EXP maintains a constant electrical current through the alarm circuit (5.0 VDC, 10 kohms), including a 10-kohm resistor. If the resistance changes, due to an electrical short or a bypass, the voltage fluctuates from its normal state. Therefore, the unit triggers an alarm.

Figure 18 illustrates the alarm and no alarm conditions of a supervised alarm input. Whether the alarm is normally closed or normally open, neither a cut nor a bypass can defeat these alarms.

NORMALLY CLOSED			NORMALLY OPEN
NO ALARM	10 K Ω		NO ALARM	10 K Ω
GND		+V	GND	+V
ALARM	10 K Ω	+V	ALARM	10 K Ω
GND			GND	+V
ALARM	10 K Ω		ALARM	10 K Ω
GND	CUT	+V	GND	+V
				CUT
ALARM	10 K Ω	+V	ALARM	10 K Ω
GND			GND	+V

BYPASS

BYPASS

Figure 18. Supervised Alarm Conditions

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