Judging the fault of a circuit through an ammeter is a very practical skill, and here are some possible ways to do it:
1.Measure the total current: Measure the total current by connecting the ammeter in series between the power supply and the load. If the total current is too high, it is possible that the load is under-circuited or overloaded. If the total current is too low, it may be that there is an open circuit in the load or that the supply voltage is too low.
2.Measure the current of the branch: connect the ammeter into each branch separately and measure the current of each branch. By comparing the magnitude and direction of the current of each branch, it is possible to determine the branch where the fault is located.
3.Measuring resistance: Connect the ammeter and resistor in series to measure the current at both ends of the resistor. If the current is too high, it may be a short circuit or overload of the resistor. If the current is too low, it may be that the resistor is open or the supply voltage is too low.
4.Measure capacitance: Connect the ammeter and capacitor in series to measure the current at both ends of the capacitor. If the current is too high, it may be that the capacitor is short-circuited or overloaded. If the current is too low, it may be that the capacitor is open or the supply voltage is too low.
5.Measuring diode: Connect the ammeter and diode in series to measure the current at both ends of the diode. If the current is too high, it may be a short circuit or overload of the diode. If the current is too low, it may be that the diode is open or the supply voltage is too low.
It should be noted that it is necessary to pay attention to safety when measuring, avoid touching live parts, and at the same time, it is necessary to select an ammeter with the appropriate range and accuracy level for measurement. Ok, here are some other possible ways:
6.Measure the power supply voltage: Connect the ammeter in parallel at both ends of the power supply to measure the power supply voltage. If the voltage is too low, it may be a failure of the power supply, or an open or short circuit of the load. If the voltage is too high, it may be that the power supply is faulty, or the load is short-circuited or overloaded.
7.Measure the pulse signal: Connect the ammeter between the pulse signal source and the load to observe the change of the pulse signal. If the amplitude of the pulse signal is too low, the signal source may be faulty, or the load may be open or short. If the amplitude of the pulse signal is too high, it is possible that the signal source is faulty, or the load is short-circuited or overloaded.
8.Measure the audio signal: Connect the ammeter between the audio signal source and the load to observe the change of the audio signal. If the audio signal quality is poor, it may be that the source is faulty, or the load is open or short. If the audio signal is completely silent, it is possible that the source is faulty, or the load is short-circuited or overloaded.
It should be noted that when using the ammeter to judge the circuit fault, it is necessary to measure and analyze it in combination with the actual situation and the circuit diagram. At the same time, it is necessary to select an ammeter with the appropriate range and accuracy level for measurement to ensure the accuracy and reliability of the measurement results. Ok, here are some other possible ways:
9.Measure motor current: Connect the ammeter between the motor and the power supply to measure the motor current. If the motor current is too high, it may be that the motor has a short circuit or overload fault. If the motor current is too low, it may be that the motor has an open circuit or the power supply voltage is too low.
10.Measure relay contact current: Connect the ammeter between the relay contact and the load to measure the contact current. If the contact current is too high, it may be a fault in the relay, or a short circuit or overload fault in the load. If the contact current is too low, it may be a fault with the relay, or an open circuit in the load or a fault with too low a supply voltage.
11.Measure the input and output current of the optocoupler: Connect the ammeter to the input and output terminals of the optocoupler respectively to measure the input and output currents. By comparing the magnitude and direction of the input and output currents, it is possible to determine whether the optocoupler is working properly.
12.Measure the input and output current of the op amp: Connect the ammeter to the input and output of the op amp respectively to measure the input and output current. By comparing the magnitude and direction of the input and output currents, it is possible to determine whether the op amp is working properly.
It should be noted that when using the ammeter to judge the circuit fault, it is necessary to measure and analyze it in combination with the actual situation and the circuit diagram. At the same time, it is necessary to select an ammeter with the appropriate range and accuracy level for measurement to ensure the accuracy and reliability of the measurement results. In addition, it is necessary to pay attention to whether the range and accuracy level of the ammeter meet the measurement requirements, so as to avoid inaccurate measurement results or damage to the ammeter due to mismatch of range or accuracy level.