User's Manual

19
PTZ Decoder Connection
 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.
 Prevent interference from high-voltage power, make reasonable wiring, and take measures
for lighting protection.
 Parallel connect 120Ω resistance to reduce reflection and ensure high signal quality.
 The Device RS-458 A line and B line cannot connect to other RS-485 output device in
parallel.
 The voltage between the A line and B line must be less than 5V.
Front-end Device Grounding
The bad grounding might result in chip damage.
No restriction for types of alarm input
The alarm input can be Always On or Always Closed.
2.5.1 Alarm Input Type
Describes alarm input and output ports.
Alarm input/output port
Name
Function
1–9
Alarm input 1~9, where 1~8 are local alarm input, 9 is a combination of
impulse and alarm (but only one function, impulse or alarm, can be
used)
C, NO
Outputs alarm signal to alarm device.
 "NO" represents normally open type.

C: Common alarm output port.
TX, RX RS-232 serial port sender and receiver that connects to RS-232 port
Ground line
CTRL 12V 12V/0.75A output with switch control
A, B RS-485 port that connects to speed dome with PTZ function.