Application of Industrial Control Computer in Broadcast Transmitter and Common Fault Handling

Nov 05, 2024 Pageview：59

Abstract: Industrial control computers have the advantages of simple operation, strong flexibility, and high reliability. With the significant improvement of China's microelectronics technology, the integration and networking level of industrial control computers have also been synchronously enhanced. At present, industrial control computers have been successfully applied in broadcast transmitters. During its operation, although it plays a very important role in value, there are also some common fault problems. This article first elaborates on the application of industrial control computers in broadcast transmitters, and then systematically studies their common fault problems and their solutions.
Keywords: industrial control computer; Broadcast transmitter; Application methods; Common fault handling
Introduction: In the process of achieving automated operation of broadcast transmitters, industrial computers play a very important role, greatly promoting the healthy development of the broadcasting and television industry. Based on this importance, it is necessary to conduct a systematic exploration of the application of industrial control computers in broadcast transmitters, as well as common faults and their handling measures during operation, to ensure that broadcast transmitters, with the assistance of industrial control computers, present higher operational quality and value.
1. Application of industrial control computer in broadcast transmitter

 
With the continuous implementation of automation in our country, the application scope of industrial control computers (IPC) in social production is becoming increasingly wide, and their value has also been greatly demonstrated. For example, after installing an industrial control computer on the equipment, the "overload protection and PSM control device" and "electronic control logic and indication device" can be automatically monitored through corresponding program control, thereby achieving automatic on-off and frequency switching of the equipment. By uploading the transmitter information to the industrial control computer on the computer room platform through a 100M network port, it is possible to receive and complete commands such as downloading operation diagrams and frequency switching on its own. This not only enables real-time communication between the computer room platform and various industrial control computers, but also wireless communication between the electronic control system and the monitoring network system. From this perspective, applying industrial computers to broadcast transmitters can significantly improve their work efficiency and performance.
2. Common troubleshooting of industrial control computers in broadcast transmitters
2.1 COM port communication is abnormal
Fault phenomenon: When communicating with other COM port devices RS-485, there may be issues such as sending but not receiving, or receiving but not sending;
Fault analysis: Usually, when programming COM communication, it is necessary to determine the communication status of the COM port in advance. The RTS communication method ensures that data can be transmitted normally when the data signal is valid, and data can be received normally when the data signal is valid. However, some users, in order to facilitate programming and speed up program execution, did not confirm the communication status of the COM port before designing the hardware, and did not pay attention to querying the sending and receiving status during programming, which is known as the AUTO communication method. Considering its universality, the COM ports on the motherboard are usually RTS communication mode, so when used for RS-485 communication, there may be faults such as sending but not receiving or receiving but not sending;
Solution: The simplest solution for this fault issue is to use EVOC product ARK-14520 (RS232 to RS485 module). However, if it is communication between COM ports on the motherboard, this problem usually does not occur.

2.2 LCD display screen does not light up
Fault phenomenon: After the chassis is powered on, the LCD display screen shows no response;
Fault analysis: The direct cause of this fault is that the LCD backlight is not lit up. After using a multimeter to measure the input power voltage of the backlight driver board inverter, the maintenance personnel found that+12V was not input. When the input power of the backlight driver board was cut off, the voltage was normal. From this, it can be concluded that this fault is caused by a short circuit in the+12V power supply on the backlight driver board;
Solution: Remove the backlight driver board with a short circuit problem from the chassis, and then power it on again to effectively solve the problem. If necessary, take some protective measures for the backlight driver board to avoid such problems from happening again.
2.3 LCD display screen does not show
Fault phenomenon one: After power on, the LCD display screen shows a "white screen" or "flower screen" phenomenon;
Fault analysis: Based on the phenomenon of the fault, the problem of the backlight not being able to light up properly has been ruled out. The reason should be that there is no data input or the LCD is not connected to the power supply. Firstly, check if there are any issues with the power supply. Using an oscilloscope to measure the RGB input data of the LCD, no abnormalities were found, but another input pin was found to have no signal. After further inspection, it was confirmed to be a Shift clock signal.
Solution: Using a multimeter to measure, it was found that the connection was not working. After connecting it, the LCD display was normal when powered on again.
Fault phenomenon 2: After power on, the LCD display screen changes from "flower screen" to "black screen", or from "white screen" to "black screen";
Fault analysis: The reason for this fault is that the LCD backlight has been lit up normally, but there is no signal input or the input signal is incorrect. This fault is usually caused by incorrect jumper settings for selecting LCD type on the motherboard or display card, or by some control leads not being connected; In addition, signal connection errors can also cause such faults, but the probability of this happening is relatively low, unless there is a mismatch problem during the LCD wiring process;

Solution: With a slight inspection by maintenance personnel, the location of the fault can be determined, and targeted troubleshooting can be carried out.
2.3 LCD display offset
Fault phenomenon: In the DOS or Windows interface environment, there are various directional offsets in the LCD display area;
Fault analysis: There are many manufacturers of the same type of LED product, and the parameters of each manufacturer may vary slightly, resulting in display area offset problems for LCDs of the same type but different brands;
Solution: Currently, some LED products are equipped with adjustment functions, and for LCDs that are not equipped with this function, the BIOS must be modified to eliminate such faults.
2.4 Workstation keyboard cannot be used
Fault phenomenon: Open the front panel door of the chassis and plug in the standard 104 keyboard. After booting up, the membrane keyboard and external standard 104 keyboard cannot be used normally;