How to use a multimeter to find short and broken circuits and leaks
Multimeter is one of the most commonly used tools for electricians, maintenance personnel, electronic engineers, hardware engineers, in the detection of electronic circuits, fault location must be less it. A small multimeter, its function is quite powerful, you can measure resistance, capacitance, diode, transistor, DC voltage, AC voltage, current, etc., to find a short circuit, circuit breakers, leakage is the most basic function of the multimeter, learn to use the multimeter, a simple fault do-it-yourself.
How to use the multimeter to find short circuit
Short-circuit measurement in electrical maintenance, component fault location is very common, measurement of short-circuit faults, must ensure that the power supply is disconnected, do not remember to operate with electricity. Short-circuit measurement using the multimeter buzzer file or ohm file for measurement, the use of the buzzer when the measurement is more intuitive, when the line is short-circuited, the multimeter will be directly "beeping", the principle of the buzzer file when the measurement of the resistance value of less than about 75 Ω, the multimeter beeping, if you want to know more accurately about the resistance between the two lines, you can use the 200 Ω file. If you want to know the resistance value between two lines more accurately, you can use 200Ω to measure. Measured using the buzzer gear, sometimes the actual internal resistance between the two signals is small, it is easy to misjudge, such as relays / contactor coils, many relays / contactor coils impedance is less than 75 Ω, the use of the buzzer gear measurement will be beeping thought short-circuit, but in fact there is not.
Engineers often use the multimeter buzzer file to quickly find the line or component short-circuit failure points, such as measuring resistance, capacitance is short-circuited, diode reverse breakdown, transistor breakdown (transistor breakdown is generally short-circuited base and emitter), integrated circuit chip power supply and ground short-circuited, a two-pin short-circuit and so on.
