How to read the meter?

The landlord came to collect the rent a few days ago, including electricity. In the evening, my husband came back and asked me if I had seen the degree on the electric meter clearly. Don't let the landlord lie to me. I said I couldn't read the electricity meter. My husband knocked on my head and gave me an output. Only then did I know that there is still so much knowledge in reading electric meters.

Electricity meters can be divided into single-phase electricity meters and three-phase electricity meters. Ordinary families use single-phase meters, villas and large power users use three-phase meters, and industrial users use three-phase three-wire meters and three-phase four-wire meters. Three-phase ammeter is divided into active ammeter and reactive ammeter, which are used to measure active power and reactive power respectively.

Ordinary direct-drive meters, single-phase meters and three-phase meters can directly read the numbers on the meters, and then subtract the last meter degree to know the electricity consumption this month. If the meter shows 123456 last month and 123789 next month, it means that it records the difference between 789 and 456, that is, the electricity consumption in that month is 78.9-45.6=33.3 kWh.

Three-phase meters are more complicated than DC meters. Connect with current transformer, with 10 meter. It is necessary to observe the ratio marked on the connected current transformer, such as 100/5 150/5. Multiplying the reading by the current ratio is the measured amount of electricity. In order to measure accurately, loss and line loss need to be added.

Single-phase ammeter measures the quantity of three-phase electricity by directly connecting the ammeter, reading the number from the ammeter and multiplying it by 3. If the ammeter is connected with a transformer, the read ammeter should be multiplied by the current multiple of the transformer and then multiplied by 3, so as to read the electric quantity of three-phase electricity.

Smart meters can be divided into single phase and three phase. Single-phase has LCD screen, which shows the total power and remaining power, and can be read directly. IC card meters can be divided into single display and double display. The LED displays a single card indicator with a little red dot. Jump to the total power consumption and remaining power, indicating that the current display is the total power consumption or remaining power.

The double display card meter can read the data of the meter above or below; Three-phase prepayment meters can be divided into direct current type and mutual inductance type. Direct current type can be read directly, while mutual inductance type needs to be multiplied by the transformer ratio to read the meter data.