The new energy vehicle testing multimeter should pay attention to the following points when measuring
(1) The new energy vehicle testing multimeter should have a large enough internal resistance, at least 10 times greater than the resistance of the circuit under test, so as not to cause large measurement errors.
(2) The meter pen or probe should take anti-slip measures. Because any instantaneous short circuit is easy to damage the integrated circuit. The following method can be taken to prevent the pen from slipping: take a section of the bicycle valve core set on the tip of the pen, and long out of the tip of the pen about 0.5 mm or so, which not only makes the tip of the pen good contact with the point being tested, but also effective in preventing slippage, even if it touches the neighbouring points will not be short-circuited.
(3) When measured a pin voltage does not match the normal value, should be based on the pin voltage on the normal operation of integrated circuits have no important impact and other pin voltage of the corresponding changes in the analysis, in order to determine the good and bad integrated circuits.
(4) IC pin voltage will be affected by peripheral components. When the peripheral components leakage, short circuit, open circuit or change in value, or the peripheral circuit is connected to a variable resistance potentiometer, then the potentiometer sliding arm is located in a different position, will make the pin voltage change.
(5) If the integrated circuit pin voltage is normal, the integrated circuit is generally considered normal; if the integrated circuit part of the pin voltage is abnormal, it should be from the deviation from the normal value of zui big place to start, check the peripheral components with or without failure, if there is no failure, then the integrated circuit is likely to be damaged.
(6) for dynamic reception devices, such as television sets, in the absence of signal, the integrated circuit pin voltage is different. If you find that the pin voltage should not change instead of large changes, the signal size and adjustable components with different positions and changes instead of changes, you can determine the integrated circuit damage.
(7) for a variety of operating modes of the device, in different operating modes, the integrated circuit pin voltage is also different.
