詳細介紹(introduction)：

       DDY79-S型電子式單相IC卡預付費電能表是我廠研制開發的集電能計量、負荷控制和用戶信息管理等多種功能的新一代產品。其電能計量部分采用本廠成熟的電子式電能表技術，整體結構合理、工藝、并具有電子式電能表的各種優點。在設計過程中，該表充分考慮到在線儀表的特點，在掉電、過壓、性和干擾能力方面采取了一系列措施，合電磁兼容性要求，產品各項性能指標合標準GB/T18460.3- 2001《IC卡預付費售電系統第3部分：預付費電度表》和標準GB/T17215-2002《1級和2級靜止式交流有功電能表》。
該產品具有體積小、功能全、性高等優點，是當前改革用電體制、實現電能商品化、解決收費難和實現用電監控及調節負荷狀態的理想產品。

 結 構：

　■ 表殼采用密封塵水結構，阻燃、老化。
　■ 1只紅色LED燈指示電量脈沖，電表每累計一個脈沖當量的電能時，脈沖燈閃爍。
　■ 電表IC卡插座在小門內，具有自保護功能，插卡時小門打開。
　■ 一路光耦隔離脈沖輸出，輸出寬度約為80ms，供校驗使用。
　■ 電量顯示采用LED數碼管方式，剩余電量等于報警電量時，LED數碼管常亮，提醒用戶及時購電。
　■ 采用IC卡作為電量傳遞介質。IC卡經過加密運算，一戶一卡，互不通用。
　■ 采用鐵電存儲器，數據保存。
　■ 采用大容量磁保持繼電器，低功耗高。
　技術參數:
　■ 額定電壓(V)：220
　■ 工作電壓范圍：70%Un～120%Un
　■ 額定電流(A)： 5(20), 5(30),10(40)
　■ 額定頻率(Hz)：50
　■ 準確度等級：1級，2級
　■ 功耗：電壓回路≤2W，10VA；電流回路≤1VA
　 ■ 工作溫度(℃)：-25～+55，限工作溫度(℃)：-45～+70
　■ 相對濕度：≤75%（年平均）
　■ 顯示范圍：0～9999kWh
　■ 數據保護：斷電后數據保存時間＞10年
　■ 外形尺寸（mm）：
　■ 平均使用壽命（年）：＞10

　功 能:

　■ IC卡預付費用電，用電量遞減。
　■ 剩余電量不足報警，剩余電量為或到達設定的賒欠電量值時，跳閘斷電提醒用戶及時購電。
　■ 負荷時自動斷電。
　■ 具有數據回寫功能。
　■ 能顯示剩余電能量以及其它各種信息

　適用范圍:

  ■ 220V 5(20)A----10(40)A為直接接入式儀表，適用于在實施或將要實施預付電費地區的城、鄉居民照明計費用表。

DDY79-S Static Single-phase Pre-payment Watt-hour Meter
Main Features
■ Using IC card; Having compositive functions of energy measurement, load monitoring and information management
■ Reasonable structure, advanced craftwork; strong anti-jamming ability; high reliability; design against voltage-interruption and over-voltage, all volume, multi-function
■ Meeting the electromagnetic compatibility requirement
■ Ideal products for energy monitoring and load adjustment of electricity network
■ All specification meeting standard GB/T17215-2002 (IEC61036-2000)on alternating current static watt-hour meters for active energy (cles 1 and 2), GB/T18460.3- 2001 on pre-payment vending system using integrated circuit (s) cards with contacts--part 3: Pre-payment electricity meters.
Structure
■ With sealed case of flame-retardant、water-proof, rust-proof and anti-aging
■ One red LED indicating power pulse and flashing once per pulse
■ Socket for IC card is designed in a all door with self-protective function; Open the door to plug the card
■ One channel of optical pulse output for calibration with width of about 80ms
■ Displaying energy by LED. When remaining energy reaches the alarm quantity, LED flashes.
■ Energy quantity is tranitted through encrted IC card
■ One card for one meter
■ Adopting FeRAM (Ferroelectric random-access memories) to ensure reliable storage
■ Large capacity magnetic-holding electrical relay, lower power consumption, high reliability
Technical Parameters
■ Rated Voltage (V): 220
■ Operation Voltage (v): 70%Un~120%Un
■ Rated Current (A): 5(20), 5(30), 10(40)
■ Rated Frequency (Hz): 50
■ Accuracy: cl1, cl2
■ Power Consumption: voltage circuit:≤2W/10VA;　current circuit: ≤1VA
■ Ambient Temperature(℃): -25~+55，limits of temperature(℃)：-45~+70
■ Relative Humidity: ≤75% (annual average)
■ Range of Display:0~9999kWh
■ Data can be stored for more than 10 years when power off
■ Size（mm）：
■ Life(year):＞10
Function
■ Prepay the energy to be used with IC card and the remaining energy will reduce continuously
■ When there is not enough remaining energy, meter will alarm. When the remaining energy reaches zero or one specified quantity, power supply is cut off to remind the user to buy energy.
■ Automatically cut off power supply when overloaded
■ Able to write back data
■ Able to display remaining energy and other information Scope of Use
■ 220V 5(20) A----10 (40) A is for direct connected meters suitable for residential energy measurement at urban or rural areas where energy prepayment has been or is to be realized