1、 Purpose and Scope of Application
DDSY6607 Dual Display Single Phase Electronic Prepaid Energy Meter（Plug in single-phase electric meter）It is a high-performance measuring instrument with a fully digital and intelligent energy metering dedicated chip as its core, combined with intelligent processing technology of single-chip microcontrollers. A new generation product with multiple functions such as fully digital energy metering, intelligent charging control, anti-theft electricity management, and user information management. This electric energy meter is an ideal product for the current reform of the electricity system, realizing the commercialization of electricity, solving the difficulty of charging fees, and regulating the load status of the power grid.

This product can be installed in indoor or outdoor meter boxes. Suitable for use in environments with temperatures ranging from -20 ℃ to 55 ℃ and relative humidity not exceeding 85%. The performance indicators of this product fully comply with the provisions of GB/T 18460.3-2001 "Prepaid Energy Meter" standard.

2、 Main functions and features
1. Standard IC card hardware encryption prepayment, the power supply department sells electricity by selling purchase cards (IC cards) to collect electricity bills in advance, and users buy first and use later.
2. Integrating multiple functions such as fully digital metering, electricity display, prepaid control, card reading, and intelligent anti-theft measures,
Has extremely high reliability.
3. Overload protection. If the load exceeds the set maximum current by 20-30% for a continuous period of time, cut off the power supply circuit. The electric energy meter will automatically close after a certain period of delay.
4. The electric IC card is encrypted multiple times through software and hardware, fully ensuring the security, correctness, and reliability of data. Through special design,
The electricity IC card records the remaining and accumulated power of the meter when the user inserts the card, as well as information on whether there is any electricity theft behavior.
5. A comprehensive checkpoint protection circuit can effectively prevent various malicious attacks on the checkpoint.
6. Display the remaining battery level to five digits (four integers and one decimal).
7. The remaining battery level reaches the pre alarm level, and the digital display flashes to indicate the remaining battery level, prompting the user to enter a new purchase amount.
8. When the remaining power in the energy meter is zero, the meter will automatically trip and interrupt the power supply. At this time, the user must bring the purchase card to the electricity sales department to purchase electricity (the power supply department can set an overdraft capacity, and after inserting the purchase card, the user can use a certain limit of electricity). After inserting the purchase card with effective electricity into the meter, the power can be supplied normally.
9. When the amount of electricity owed reaches a certain value, the power will automatically be cut off. After inputting new purchased electricity (deducting the overdrawn electricity), the power supply will be automatically restored.
10. The application of magnetic holding relays improves the reliability of power-off actions and reduces power consumption after power-off actions,
At the same time, it also overcomes the problem of contact adhesion when the relay works for a long time with high current.
11. Automatically save data during power outages and restore data automatically upon incoming calls.
12. The electricity sales management system consists of a computer, a dedicated IC card reader/writer, and billing management software.
13. By comparing and analyzing the recorded information, the management system can list users suspected of stealing electricity, in order to focus on
Check and reduce the workload of preventing and detecting electricity theft.
14. Display instructions: When the electric energy meter is powered on, insert the IC card in reverse, and the serial number and content are shown in the table below.

Serial Number	content
00	State of charge
01	Total Power
02	Current power

3、 Specifications and main technical parameters
1. Compliant with the national standard GB/T18460.3-2001;
2. Rated voltage: 220V;
3. Calibration current: 5 (20) A; 10(40)A； 15(60)A ； 20(80)A；
4. Rated frequency: 50Hz;
5. Environmental conditions:
The standard operating temperature is -20 to+45 ℃
The maximum working temperature is -30 to+55 ℃

6. Relative humidity ≤ 85%;

4、 Working principle and structure
4.1 Working principle:
As shown in Figure 1, the electric meter mainly consists of two functional modules: one is the energy metering unit, which uses large-scale dedicated integrated circuits to convert current and voltage into pulses proportional to active energy, achieving energy metering; The second is the data processing unit, which uses a dedicated single-chip microcomputer processor to complete functions such as energy metering, data processing, card reading and writing display, and load control.
4.2 Structure
The shell of the electric energy meter consists of several parts, including the base, upper cover, and terminal box cover. The upper cover and terminal box cover are respectively sealed with lead,
There is an IC card socket on the right side of the upper cover.
The energy meter panel has an LCD for displaying electricity usage information, alarm information, and operation prompt information.
5、 Prepaid energy meter LCD display
The LCD display of the prepaid energy meter works in reverse counting mode, with a minimum display decrease unit of 0.1 kWh. When remaining
When the power is 0 kWh, the power will be cut off once, and the user can continue to use the power after inserting the power card. The digital display decreases to a negative value to remind the user to enter a new purchase amount. When the negative value reaches a certain value (which can be set before leaving the factory, usually -10kWh), the power will be automatically cut off, and power will be restored after inputting new purchased electricity. When the remaining battery level is less than the alarm value, the remaining battery level flashes and displays.
6、 Usage method
1. Users can purchase electricity on the dedicated microcomputer of the local power supply department with their purchase card, and the selling machine will write encrypted information and the amount of electricity purchased into the purchase card.
2. After purchasing electricity, the user inserts the purchase card (with the color printed side facing inward, in the direction of the arrow) into the IC card slot of their energy meter for a few seconds (fully inserted). After reading the purchased electricity amount, the purchase card is removed (LCD displays the purchased electricity amount), and the energy meter simultaneously writes the electricity consumption on the user's purchase card. Successfully display "□", then display the remaining battery level, otherwise the energy meter will display an error message of "E". When the user purchases electricity again, the write back data is read by the management system for electricity management.
3. Provide special function cards such as reset cards and power cutoff cards for the sales and power supply management departments. This type of card is generally restricted for use.

4. It is strictly prohibited to insert damp cards into the meter.

7、 Installation
1. The electric energy meter can be installed and used after passing the inspection before leaving the factory and being sealed with lead;
2. The electric energy meter should be installed indoors or outdoors inside the meter box, and the bottom plate of the meter should be fixed on a sturdy and fire-resistant wall. It is recommended to install it at a height of about 1.8 meters, and there should be no corrosive gases in the air;
3. The electric energy meter should be wired according to the wiring diagram on the terminal box, preferably using copper wire or copper wire connectors;
4. The unit of electrical energy displayed on the LCD of the energy meter is kWh;
5. Installation dimensions; 88X142mm.

6. Dimensions: 108X168X64mm.

8、 Transportation and storage
1. The transportation and unpacking of electric energy meters should not be subjected to severe impacts, and should be transported and stored in accordance with the provisions of GB/T15464-1995 "General Technical Conditions for Packaging of Instruments and Meters".
2. The energy meter should be stored in its original packaging in an environment with a temperature range of -25 ℃~70 ℃ and a relative humidity not exceeding
80%, no corrosive gases in the air; The electric energy meter should be stored in the warehouse and placed on the rack