Yesterday, I worked on a Changhong 2539A TV set. The main IC was TDA9373. When I turned it on, the image was extremely dark. I tried adjusting both brightness and contrast to their maximum settings, but there was no improvement. I checked the backlight voltage, which was 4.2V, and the acceleration voltage was 340V. The RGB voltages were around 175V each, which seemed normal. Then I measured the reverse input pin 34 of the large block, which was at 0.5V. Normally, this pin should have a pulse signal, but even without it, it wouldn't cause the screen to be completely dark or black. Next, I checked the black current detection terminal, pin 50, which had a voltage of 5.5V—this was fine. I then focused on the ABL circuit. Looking at the data sheet, pin 49 was supposed to receive the ABL input. The measured voltage at pin 49 was only 1.6V, which was lower than expected. I tried lifting the pin slightly, and the voltage increased to 3.8V, which made the picture brightness almost normal. This confirmed that the issue was in the ABL circuit. Further inspection showed that diode VD485 had abnormal resistance on both directions, indicating some leakage. I also found that resistor R485 was open during testing—its resistance was over 700kΩ, whereas it should have been around 100kΩ. After replacing the diode and the resistor, the voltage at pin 49 rose to 3.6V, and the TV worked properly after rebooting. The repair was successful.
Aluminum core Solar Cable is a photovoltaic circuit using aluminum as a conductive material. It is widely used in solar power generation systems to transport the electricity generated by solar panels.
Compared with traditional copper solar cable, aluminum solar cable has some obvious advantages, the most important of which is low cost.
1. Low price: Aluminum is a common metal, and its price is cheaper than that of copper. Therefore, the use of aluminum solar cable can reduce the cost of the system and make the entire photovoltaic power generation project more economical.
2. Lightweight: Aluminum has a lower density and is lighter than copper. The aluminum core optical cable can reduce the weight of the cable and facilitate installation and maintenance.
3. Strong corrosion resistance: Aluminum has good corrosion resistance and can maintain a long service life under harsh environmental conditions. This makes the aluminum solar cable more reliable for outdoor use.
4. Excellent conductivity: although the conductivity of copper is higher than that of aluminum, the aluminum solar cable can make up for the shortcomings of the low conductivity of aluminum to a certain extent by optimizing the design and process and ensure the efficiency and stability of power transmission.
It should be noted that there are also some limitations and precautions for aluminum solar cable. Due to the low conductivity of aluminum, the resistance of the aluminum solar cable will be relatively high, so it is necessary to choose the wire diameter and length reasonably when designing and installing to ensure the efficiency of power transmission. In addition, aluminum is prone to electrochemical reactions when it comes into contact with copper, so corresponding measures need to be taken when connecting aluminum solar cable and other components, such as using special connectors or coating protective layers.
In general, aluminum solar cable with its low cost, corrosion resistance, light and other advantages, has been widely used in solar power generation systems, and brings economic and reliability benefits to photovoltaic power generation projects.
Aluminum Solar Cable,Photovoltaic Solar Cable,TUV Aluminum solar cable,Aluminum Energy Cable
Suzhou Yonghao Cable Co.,Ltd. , https://www.yonghaocable.com