The following are the eight test methods and procedures for radar level gauges:
1. Tapping pressure method
It is often encountered that the instrument is running well or not, which is mostly caused by poor contact or solder joints. For this case, tapping and hand pressing can be used.
The so-called "knocking" is to gently knock the board or part through a small rubber hammer or other tapping object to see if it will cause an error or a downtime. The so-called "hand pressure" is when the fault occurs, after the power is turned off, the inserted components and the plug and the seat are again pressed by hand, and then the power is turned on to try to eliminate the fault. If you find that the shell is normal, and then knocking is not normal, * good first, then all the joints are re-inserted and try again. If the brain is unsuccessful, you have to find another way.
2, observation method
Use vision, smell, and touch. In some cases, damaged components will change color, blister or burnt spots; burnt devices will produce some special odor; short-circuited chips will be hot; visible or desoldered parts can also be observed with the naked eye. .
3. Exclusion method
The so-called elimination method is a method for judging the cause of the failure by plugging in some boards and devices inside the machine. When the instrument returns to normal after removing a board or device, the fault has occurred there.
4, replacement method
Two instruments of the same model are required or there are enough spare parts. Replace a good spare with the same component on the faulty machine to see if the fault is eliminated.
5, comparison method
Two instruments of the same model are required and one is in normal operation. Use this method to have the necessary equipment, such as a multimeter, oscilloscope, etc. According to the nature of the comparison, voltage comparison, waveform comparison, static impedance comparison, output comparison, current comparison, etc.
The specific method is: let the faulty meter and the normal meter run under the same conditions, and then detect the signals of some points and then compare the two sets of signals measured. If there are differences, it can be concluded that the fault is here. This method requires the maintenance personnel to have considerable knowledge and skills.
6, lifting temperature method
Sometimes, the instrument works for a long time, or when the working environment temperature is high in summer, it will malfunction, the shutdown check is normal, and it will be normal after stopping for a while, and then it will malfunction after a while. This phenomenon is caused by the poor performance of individual ICs or components, and the high-temperature characteristic parameters fail to meet the requirements of the index. In order to find out the cause of the malfunction, the temperature rise and fall method can be employed
The so-called cooling, that is, when the fault occurs, use cotton fiber to wipe the anhydrous alcohol in the part that may be faulty, to cool it, and observe whether the fault is eliminated. The so-called heating is artificially raising the ambient temperature, such as using a soldering iron to close the suspected part (be careful not to raise the temperature too high to damage the normal device) to see if the fault occurs.
7, riding the shoulder method
The shoulder method is also called parallel method. Place a good IC chip on the chip to be inspected, or connect good components (resistance capacitors, diodes, transistors, etc.) in parallel with the components to be inspected, and keep in good contact. If the fault is caused by an open circuit inside the device or If the contact is not good, etc., this method can be used to eliminate it.
8, capacitor bypass method
When a circuit produces a strange phenomenon, such as a display disorder, the capacitor bypass method can be used to determine the portion of the circuit that is likely to fail. Connect the capacitor across the power supply and ground of the IC; connect the transistor circuit across the base input or collector output to observe the effect on the fault. If the capacitor bypass input is inactive and bypasses its output, the fault disappears. By following the above steps on the radar level gauge, it is safer and safer to use!
Milling machining is to fix the blank, using a high-speed rotating milling cutter on the blank to cut out the required shape and characteristics.Conventional milling is widely used to milling profile, groove and other simple shape features.CNC milling machines can be used to process complex shapes and features.The milling and boring center can carry out three or more axes milling and boring processing, which is used for processing, mould, inspection tool, placenta, thin wall complex surface, artificial prosthesis, blade, etc.When selecting the content of nc milling, the advantage and key role of nc milling machine should be given full play.
CNC Milling Machine,Aluminum CNC Milling Machining,5 Axis CNC Machining,5 Axis CNC Milling Machine
YaoPeng Metal Products Co., Ltd. , https://www.ypmfg.com