Optical path and interface problems during installation of video optical transceivers

The installation of video optical transceivers is a prerequisite for the use of optical transceivers, so the installation process is more important. With more and more applications of video optical transceivers, customers have encountered many problems in the installation of video optical transceivers. This article describes the optical and data interface problems in the optical transceiver installation process.

First, on the optical path of the video optical transceiver installation

In the security monitoring project, most of the optical cables are laid by users themselves, generally single-mode optical fibers. Since the system coverage is generally not large, the optical link loss of the equipment with standard (≤20KM) equipment is very plentiful. Therefore, the video optical transceiver does not require excessive optical path loss, but users often encounter no image, image jitter, Like snowflakes and poor image quality, most of the problems are at the pigtails, jumpers, or adapters at the ends of the light path, and very little about the trunk light path.

Common problems include:

1. Incorrect insertion of fiber optic connector;

2. The fiber optic connector core (ceramic tube) is contaminated.

The solution is:

1. Reinsert the active connector or swap the fiber jumper;

2. Wipe the plug with 99.9% absolute ethanol and plug the core;

3, check the camera video cable with a multimeter to determine whether there is a video signal;

After the above process will generally solve the problem. If conditions permit, the optical path loss can be measured with an optical fiber tester or optical power meter.

Second, on the data interface of video optical equipment installation

In order to meet the needs of security monitoring, the system's various devices (matrix, hard recorders, decoders) provide RS-485 data interface. The advantage of this format of data interface is long transmission distance, strong load capacity, and 4-wire 485 A four-wire full-duplex communication bus can also be formed, and any two devices on the line can implement two-way communication. Many devices and PTZ are easy to connect and use 2 lines of 485. If there is no communication (runaway), look for the following reasons:

1. Check whether the HD video recorder sets the PTZ address correctly, and whether it corresponds to the address set by the decoder dial switch.

2. Check whether the video optical transceiver data port wiring is correct. Generally, the data interface wiring definition of each optical transceiver manufacturer is not the same. It must be connected according to the instruction manual.

3, detect whether there is a control signal. Use a multimeter to communicate 10V measurement controller (matrix, hard record, etc.) to output RS-485 port to see if it has control signal output.

4. It is judged whether the RS-485 interface of the video optical transceiver is normal. If the voltage between the positive and negative lines is zero, it is regarded as abnormal.

5. The normal operation of the system is occasionally out of control because the system is in a critical state. It is necessary to increase the load capacity of the controller (such as the access code expander), improve system impedance matching, and improve the material quality.

6. The data cable from the video transmitter to the gimbal should not exceed the allowable length. Otherwise, the line loss will be too large to control the gimbal.

The above is about the introduction of common problems in the installation process of video optical transceivers. If you still encounter other problems, please contact us!