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User's Manual
29
3.4.1 Alarm Connection
Before using the alarm, connect alarm input or alarm output device.
3.4.1.1 Connection
The section introduces alarm connection of the Device.
Alarm Input
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Both NO and NC are supported.
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The alarm input port supports alarm signal from ground and device of 12-24 V voltage.
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If the alarm device is connected to the Device and other devices, use relay for isolation.
Alarm Output
The alarm output port cannot be connected to high-power load (less than 1A). When forming output
circuit, the excessive current should be prevented from causing damage to the relay. Use the
contactor for isolation when applying high-power loads.
PTZ Decoder Connection
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The common-ground must be prepared for PTZ decoder and the Device; otherwise the common-
mode voltage might not be able to control the PTZ. It is recommended to use shielded twisted
pair, and the shielding layer can be used for common ground.
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Prevent interference from high-voltage power, make reasonable wiring, and take measures for
lighting protection.
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Remotely import 120 Ω to reduce resistance reflection and protect the signal quality.
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The Device A line and B line cannot connect to other RS-485 output device in parallel.
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The voltage between the A line and B line of PTZ decoder must be less than 5 V.
Notes to Grounding
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Poor grounding of camera might damage the chip.
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When supplying external power source to the alarm device, the alarm device should be
common-grounded with the Device.