1. Purpose Characteristics and scope of adaptation

The DTSY1791 series plug-in three-phase electronic prepaid energy meter is a new type of instrument manufactured by our company using imported specialized large-scale integrated circuits, 16 bit A/D conversion, digital multipliers, digital sampling processing technology, and a single-chip processing system for data acquisition, processing, and storage, as well as SMT technology. Suitable for measuring the consumption of active energy in three-phase three wire or three-phase four wire AC power grids with a rated frequency of 50Hz or 60Hz. The product meets all technical requirements of GB/T17215.321-2008 "Level 1 and Level 2 Static AC Active Energy Meters" and GB/T 18460.3-2001 "IC Card Prepaid Electricity Sales System Part 3: Prepaid Energy Meters".

Main features: Application of computer management,Purchase electricity first and then use itWithin the rated current range, the maximum operating power can be limited (by the power supply department); One meter, one card, dedicated card, no power loss after card loss, can be used after card replacement; Electric cards can transmit data bidirectionally and automatically power off to alert users when purchasing electricity; When the battery level is zero, the power will automatically trip and cut off; And it has certain anti-theft software design, etc.

This meter is designed for fixed installation indoors and is suitable for environments with temperatures not exceeding -20 to+55 ℃, relative humidity not exceeding 85%, and free from corrosive gases in the air, as well as to avoid the influence of dust, mold, insects, etc.

2.Specifications, models, and technical indicators

2.1Specification and model

2.2Basic Error (Balance Load Error Limit)

Note: (Ib rated current Imax maximum current)

2.3start

Under the conditions of reference voltage, reference frequency, and COS φ=1.0, the instrument should be able to continuously measure electricity with a load current of 0.004Ib (level 1) and 0.005Ib (level 2).

2.4Stealth

When the rated voltage of the voltage circuit is 115% and there is no current in the current circuit, the test output of the instrument should not generate more than one pulse.

2.5Voltage range

Normal operating voltage: 0.9Un-1.1Un

Maximum operating voltage: 0.8Un-1.15Un

2.6power waste

Voltage line power consumption: ≤ 2W and 10VA

Current line power consumption: ≤ 4.0VA

3.working principle

3.1Working principle block diagram

The electric energy meter obtains voltage sampling signals from the voltage divider, current sampling signals from the current transformer, voltage current product signals from the multiplier, and then generates a counting pulse with frequency proportional to the product of voltage and current through frequency conversion.

3.2data processing

The electric energy metering pulse is sent to the CPU for processing through a photoelectric coupler, and after calculation, it is stored in a non-volatile EEPROM. The information system is managed by a computer, and through an IC card reader/writer, a certain amount of electricity and monitoring requirements are written into the IC card input table of the microprocessor system. After being processed by the CPU, it provides display, alarm, and cut-off status signals.

4.Installation and use

4.1 The electric energy meter can be installed and used after passing the inspection and being sealed with a lead seal before leaving the factory. Electric energy meters without lead seals or stored for too long should be re inspected by relevant departments before installation and use.

4.2 The electric energy meter should be installed in a ventilated and dry indoor area, and can be installed at any position. However, it is usually installed vertically, with a recommended installation height of about 1.8 meters

The bottom plate of the watch should be fixed on a sturdy, fire-resistant, and vibration resistant wall.

4.3 In places with pollution and potential damage to the structure, the electric energy meter should be installed in a protective cabinet.

4.4 When installing wiring, follow the wiring diagram on the terminal knob cover of the electric energy meter or the corresponding wiring diagram in this manual. It is best to use copper connectors to prevent the electric energy meter from burning out due to poor contact.

When using an electric energy meter in areas with frequent lightning strikes, lightning protection measures should be taken to avoid damaging the meter due to lightning strikes.

4.6 The load capacity of the electric energy meter is between 0.05Ib~Imax (direct connection type) or 0.02Ib~Imax (through transformer connection type). Exceeding this load capacity will result in inaccurate measurement of the electric energy meter or burning of the current coil due to heating.

4.7 The reading of an electric energy meter connected through a transformer must be multiplied by the transformation ratio to obtain the actual amount of electricity.

4.8 One table, one card: The IC card held by the user cannot be exchanged. In case of loss, a replacement card should be purchased from the power supply department (i.e. the electricity sales office).

4.9 Preparation for purchasing electricity: The user must insert the IC card into the card slot once to facilitate the return of data from the meter to the computer database.

4.10 Electricity purchase method: When selling electricity, insert the IC card into the IC card reader and operate the computer to encrypt the user ID, pre purchased electricity, capacity limit method, and power limit into the IC card.

4.11 Electricity Card Usage: Insert the power purchase card into the card slot. If it is a valid power purchase card, the meter will automatically read the data into the meter. The LCD (LED) display screen will show the following in sequence: purchased electricity quantity (P0==XXXX), total purchased electricity quantity (P=XX XXXX), purchased electricity times (PC=XXXX), alarm electricity quantity (P1==XXXX), credit limit (P2=XXXX), and limited capacity power (F0X=XX: XX). Please store the unplugged card properly.

4.12 Operation Display: During the operation of the energy meter, the display screen alternately shows the remaining power and total electricity consumption in the meter.

4.13 Overcapacity alarm: During the operation of the electric energy meter, if the "alarm indicator light" flashes rapidly, it warns the user that the electricity has been exceeded; If the user is set to the over capacity power-off limit mode, after 30 seconds of over capacity power consumption, the switch will be turned off for 3 minutes and displayed in a countdown (180 seconds) to restore power supply; If the user inserts the card and responds, the power supply can be immediately restored.

4.14 Accumulation limit: If the purchased electricity+remaining electricity>accumulated electricity (10000kWh), the purchased electricity will not be read in, and the display will show a "remaining limit" prompt, indicating that the electricity in the card is still valid.

4.15 Warning Reminder: When the remaining battery level in the meter is less than twice the "alarm battery level", the "alarm indicator light" will flash (with an interval of 1 second) to remind the user to purchase electricity. At this time, if the user responds by inserting a card, the "alarm indicator light" will flash at an interval of 2 seconds to avoid power outage warnings.

4.16 Power outage warning: If the user does not respond by inserting the card during the warning reminder and sets an over capacity alarm, when the remaining power is the user's agreed alarm power (or 10% of the purchased power), the energy meter will pull off the power outage warning and display the "pull off" prompt. At this time, inserting the IC card into the card slot once will restore power supply. If the IC card of this meter cannot be found after pulling the switch, you can borrow a neighbor's IC card to insert it and restore power supply.

4.17 Power purchase reminder: When the remaining power in the meter is less than the "alarm power", the "alarm indicator light" will remain on as a constant reminder.

4.18 Fault declaration: When the remaining power is displayed as zero or negative, a "trip" prompt will be displayed. If the energy meter continues to operate, the user should immediately purchase electricity and proactively report the situation to the power supply bureau.