This site2017-03-31 17:28:28
The surface of the instrument can be seen with the naked eye. If it is a problem with the internal components, the damaged components will generally change color. Bubbles or spots may appear, and special odors may be caused. The short-circuited chip will be hot.
2. Fault state adjustment method
For toxic gas detectors, generally, do not touch the components in the circuit, especially adjustable devices, such as potentiometers, before the fault is determined.
Users often encounter ups and downs during the operation of the instrument, most of which are caused by poor contact or welding. In this case, percussion can be used.
The so-called "knock" is to gently tap the card or component with the hand or other items to see if it may cause an error or a shutdown failure. If the tap is found to return to normal after the tap is found, then the tap is abnormal. Turn off the power and re-plug all plug parts firmly, and then turn on the machine to see if the fault will be eliminated.
4. Isolation and exclusion
According to the fault detection flow chart, pull out some plug-in boards and components in the plug-in machine to determine the fault, and gradually narrow the search range, and then cooperate with the method of signal comparison and component exchange to generally find the fault.
5. Replacement method
Requires two instruments of the same model or sufficient spare parts. Replace a good spare part with the same component on the faulty machine to see if the fault is eliminated.
6. Parallel method
Install a good IC chip on the chip to be inspected, or connect a good component in parallel with the component to be inspected, and maintain good contact. If the failure is caused by an internal open circuit or poor contact, etc. Methods can be excluded.
7. Cooling method
Sometimes, the instrument will work for a long time, or the environment will have a high temperature, and it will malfunction. It is good to use it for a while. This phenomenon is due to the poor performance of individual ICs or components, and the high-temperature characteristic parameters cannot meet the requirements of the index. In order to find the cause of the failure, a cooling method can be used.
The so-called cooling down is to wipe down the alcohol that may fail with cotton fiber when the failure occurs, and then cool it down to see if the failure is eliminated.