How to use a multimeter to determine if the earth wire is properly earthed
A multimeter cannot be used to measure whether the ground is properly grounded.
It is necessary to use a special ground resistance measurement instrument. But a simple measurement can still be done, as long as the firewire and ground between the access to a 200W or more load, then measure the actual voltage on the load, if the voltage can reach 200V or more, it shows that the earth wire has been grounded. The higher this voltage is, the better the wiring is.
Grounding is the neutral point of the power system and electrical devices, electrical equipment, exposed conductive parts and devices outside the conductive part of the conductor through the conductor connected to the earth. It can be divided into work grounding, lightning protection grounding and protective grounding.
Multimeter is a multi-function, multi-range measurement instrument, general multimeter can measure DC current, DC voltage, AC current, AC voltage, resistance and audio level, some can also measure AC current, capacitance, inductance and semiconductor parameters (such as β) and so on.
The multimeter is composed of three main parts: the meter head, the measurement circuit and the changeover switch. Multimeter is the most basic tool in the field of electronic testing and a widely used testing instrument.
Multimeter has the advantages of multi-purpose, wide range, easy to use and so on, it is the most commonly used tool in electronic measurement. It can be used to measure resistance, AC and DC voltage and DC voltage. Some multimeters can also measure the main parameters of the transistor and the capacitance of the capacitor. Mastering the use of multimeter is a basic skill of electronic technology.
Common multimeters are pointer multimeters and digital multimeters. Pointer multi-meter is a head for the core components of the multi-function measurement instrument, the measured value by the head pointer indication reading. Digital multimeter measurement value by the liquid crystal display directly in the form of digital display, easy to read, some also with voice prompts.
The DC current file of the multimeter is a multi-range DC voltmeter. The head of the meter can be connected in parallel with a closed-circuit voltage divider resistor to expand its voltage range. The DC voltage of the multimeter is a multi-range DC voltmeter. The voltage range of the multimeter can be enlarged by connecting a voltage divider resistor in series with the head of the meter. Different voltage divider resistors have different ranges.
