LCD three-phase plug-in electricity meter, LCD single-phase plug-in electricity meter principle and installation

LCD three-phase card power meter, LCD single-phase card power meter principle and installation - main technical indicators
Single-phase card prepaid power meter
The actual measurement error of the accuracy level is not greater than the national standard.
Reference working voltage/can work normally under voltage to ensure measurement accuracy.
Operating current.
The power consumption of the voltage loop uses liquid crystal display to display the power consumption
Normal operating temperature range ℃℃ Extreme operating temperature range ℃℃. The electric energy meter can work normally and the error will not exceed 1 hour when placed in an environment with a humidity of ℃.
Using digital tube to display the display range.
The watch case is made of flame-retardant material with certain strength, deformation and aging resistance. The watch cover is made of polycarbonate material. The terminals are made of bakelite material. The nameplate is made of aluminum. It is resistant to sunlight and will not fade or deform during its lifetime.
With anti-static attack function, the energy meter can work normally when using a high-voltage attack power supply of more than 10,000 volts, such as the cover card holder and other places!
The average service life is more than one year.
It has various functions to prevent electricity theft, including bridging electricity theft and leakage, opening the cover to change the internal resistance and network electricity theft.
Using international standard cards and the card has a unique encryption algorithm to ensure that users cannot steal electricity through the card.
Has the ability to withstand even and odd harmonics.
Meet all national standards except the above requirements.
Three-phase card prepaid energy meter
The accuracy level is based on the basic error. The actual error is not greater than the national standard.
Reference working voltage/can work normally under voltage to ensure measurement accuracy.
Operating current.
Power consumption of each phase voltage circuit
Normal operating temperature range ℃℃ Extreme operating temperature range ℃℃. The electric energy meter can work normally and the error will not exceed 1 hour when placed in an environment with a humidity of ℃.
Using digital tube to display the display range.
The average service life is more than 1 year.
If any one or two phases among the three phases are missing, the missing zero line can be accurately measured. It can also accurately measure only any two phases and the zero line is missing.
Using three light-emitting diodes for three-phase power indication, any fault in the voltage loop or current loop of any of the three phases can be indicated.
There is a missing (reverse) phase indication.
In order to prevent damage to a certain phase circuit and missing electricity, three slices or separate phases are used to measure the total electricity consumption instead of the sum.
It has the function of preventing reverse connection and electricity theft. When one of the three phases is continuously reverse-connected and steals electricity for more than half an hour, the meter automatically converts to an absolute value sum operation until normal power consumption occurs for several consecutive hours, and then converts to an algebraic sum operation.
Using industrial grade devices.
Using international standard cards and the card has a unique encryption algorithm to ensure that users cannot steal electricity through the card.
Has the ability to withstand even and odd harmonics.
Meet all national standards except the above requirements.
The working principle and function of each part of the card prepaid energy meter
The energy measurement part uses the energy measurement module. Its working principle is that the voltage divider completes the voltage sampling and the sampling resistor completes the current sampling. The voltage and current signal after sampling is converted into a power signal by a multiplier. After/conversion, a pulse sequence indicating the amount of electricity is generated. The high-frequency electric energy pulse represents the instantaneous active power. After the power is isolated by the optical couple, the output is used as a calibration pulse and the light-emitting diode in series with the optical couple can be used for electric energy measurement indication. After frequency division and driving, it becomes a low-frequency electric energy pulse. Low-frequency electric energy pulse is also called electric energy pulse. By accumulating this pulse, the active electric energy can be calculated. Therefore, this pulse is isolated by the optical couple and sent to the microprocessor for electric energy measurement. The electric energy metering module is equipped with anti-sneak logic and anti-stealing functions. When the electric energy pulse is lower than a certain value, its output is turned off to anti-sneak current channels. The current channel is equipped with a chopper circuit so that the output of the multiplier is not only related to the magnitude of the measured current and voltage. And related to its phase, it can identify the forward and reverse active power, and also output electric energy measurement pulses for normal measurement when the active power is in the reverse direction.
Microprocessor The microprocessor (i.e. single-chip microcomputer) serves as the card and LCD interface and also serves as power theft detection and overload control. The buzzer will sound when there is power theft or overload.
The microprocessor transfers data to the encrypted card through the card interface. The microprocessor provides status display and alarm signals after calculation. Users need to pay for electricity at the power supply department. The purchased electricity is written into the user card on the selling motor and passed to the energy meter card. After being encrypted multiple times, it can ensure reliable use by users. When the purchased power is used up, the power-off mechanism in the meter will automatically cut off the power supply circuit. For users, one meter and one card (power purchase card) are used to create the content on the card. In addition to the electricity purchased each time, the number of electricity purchases and the number of electricity recharges can be compared with the data in the table and the data is encrypted by algorithm. Anti-theft function. For the electricity sales department, there are also set-up cards for meter reading, meter replacement, and universal cards. The setting card can set the constants of the electric energy meter or reset the data in the meter to zero. The meter reading card can read back the data in the meter, such as the accumulated power, remaining power, overloaded power, maximum load, etc. The data in the meter can be read at one time. The meter changing card can rotate the meter. The data is converted to the rotation table and the multi-purpose card is used for debugging. The power can be set for testing. In order to distinguish these cards, there are two signals, namely the setting signal and the card change signal.
The electricity sales management system saves all the original data of the user. When the card is lost or damaged, you can apply for a replacement card at the electricity sales system outlet.
Non-volatile memory In order to permanently save important data when the AC power is cut off and restore the data when power is turned on, the microprocessor expands the non-volatile memory through the serial peripheral interface. The non-volatile memory adopts serial, which has online fast read/write function and can be erased and written more than 10,000 times, and the data can be retained for years.
Liquid crystal display electronic energy meter adopts liquid crystal display. Liquid crystal display is divided into general type and special type. The universal type generally has its own controller and driver in addition to the display screen. It is easy to use and relatively expensive. The special type generally only has a display screen. The display screen is designed according to the application and displays characters and symbols without a controller or driver. The special type is cheap and difficult to program, requiring additional controllers and drivers. Most of the LCD displays of electric energy meters are special-purpose.