Dante DLM1771, Инструкция по установке и эксплуатации

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→DVR control protocol is not compatible with the product or the function is not
complete.
Problem: why does the same pan tilt have different control speeds at different hard
disk video recorder?
→Speed command codes in control software of DVR are different.
Problem: DVR may not control speed of pan tilt
→Control command code of control software in DVR only has a fixed speed.
Problem: the camera rotates disorderly. The image is blackish or whitish.
→There is interference with the RS-485 lines, check the equipment in the lines
such as optical transmitter and receiver.
Problem: the pan tilt camera may be controlled normally in the morning and evening,
but it may not be controlled at the noon of summer.
→High temperature may cause lower down of control line anti-jamming or change
to control equipment and CMOS chips parameters to create problems. Check if the
temperature is over than the specified limit and if fan is functioning.
Problem: pan tilt camera continuously does self-check up after power on
→The supply voltage is too low or the power is not enough. The matching
transformer of 3.5A 24VDC (if VDC was specified) is recommended. The
installation distance should be no more than 30m.
3. Installation
Problem: what is the maximum distance of video wire and what requirements does it
have to wire materials?
→The video wire also has inner loss as the power wire. The more the wire is and
the small the specification is, the worse loss it will be. The high the signal
frequency is, the obvious the loss is. The normal video wires models and the MAX.
Transmission distance is listed in following table:
Video
wire
model
Max. distance Video wire model Max. distance
75-2 About 150m 75-5 About 370m
75-3 About 200m 75-7 About 500m
75-4 About 270m 75-9 About 680m
Problem: what wire and transmission distance should RS-485 control line take?
→Transmission distance of RS-485 is related to wire diameter and transmission
speed. Max. Transmission distance for RS-485 is 1200m according to the specified
9600b/s transmission speed for 1.0mm 2 UTP.
Remarks: the same model wires may be different for produced by different
manufacturers. Above data is the normal wire transmission
reference distance.