详细介绍(introduction)：

    DDSF879系列电子式单相多费率电能表是我厂为满足市场需求而研制开发的计量新产品，该产品采用国外先进的电能计量芯片、高性能的CPU、RTC时钟芯片、显示器（计度器）以及SMT先进工艺制造。其特点是对电量能根据不同时段分别计量，具有四费率、十二时段、防窃电、高、高可靠性、高过载、低功耗、重量轻等优点。尖、峰、平、谷费率及各时段可按需要设定。

    电能表采用专用滤波网络，具有较强的抗干扰能力。

    本产品采用国家标准GB/T 17215-2002《1级和2级静止式交流有功电能表》、GB/T 15284-2002《多费率电能表 特殊要求》、电力行业标准DL/T 614-1997《多功能电能表》等。电能表具有红外通信口和RS485通信口，通信规约符合电力行业标准DL/T 645-1997　《多功能电能表通信规约》。生产本产品的质量管理体系通过了GB/T 19001(ISO9001)。

    供电部门可利用专用的编程器通过红外或RS485接口设置费率时段、时间日期、编　　程密码等等内容；通过专用的抄表器读取电能表上除密码外的各种信息，并在合法授权　　下进行对时。红外通信距离不小于 4米 ,通信角度不小于15°。抄表器可将数据传给计算机。用户可根据需要选配EIA-RS485接口。

　　注：其中LCD液晶显示的载波多费率电能表具有电力线载波抄表、远程负荷控制的功能。

　　结 构：

　　■ 表壳采用密封防尘结构，阻燃、抗老化。
　　■ 具有红外通信口和RS485通信口。
　　■ 1只红色LED灯指示电量脉冲，电表每累计一个脉冲当量的电能时，脉冲灯闪烁。
　　■ 一路光耦隔离脉冲输出，输出宽度约为80ms，供校验使用。
　　■ 采用长寿命、超亮度LED灯作时段指示。
　　■ 电量显示采用双计度器、LCD液晶显示和LED数码管显示三种形式。在正常使用条件下，其显示器的寿命大于10年。
　　■ 工作电源采用变压器隔离。
　　■ 在电表内有编程控制开关，在接线端子块上装有电量脉冲输出口和RS485接口。

　　技术参数：

　　■ 额定电压(V)：220，230
　　■ 工作电压范围：70%Un～120%Un
　　■ 额定电流(A)：5(20) , 5(30), 5(50),10(40), 10(60) ,15 (60) ,15(90),20(80) ,10(100)
　　■ 额定频率(Hz)：50，60
　　■ 准确度等级：1级，2级
　　■ 功耗：电压回路≤2W，10VA；电流回路≤1VA
　　■ 工作温度(℃)：-25～+55，极限工作温度(℃)：-45～+70
　　■ 相对湿度：≤75%（年平均）
　　■ 费率：二/三/四种费率可选；时段：≥8
　　■ 时钟：0.5s/d( 23℃ )，随温度变化改变量优于0.1s/ (d·℃)
　　■ 电池容量（Ah）：≥1Ah,维持时钟正常工作不少于10年
　　■ 外形尺寸（mm）：（LCD、LED显示）；（双计度器显示）。
    ■ 平均使用寿命（年）：＞10

   功 能

　　■ 计量正、反向有功电能，反向电能按正向累计。
　　■ 电能量按总、尖、峰、平、谷分别累计和存储。
　　■ 具有自动抄表功能,指定每月某天的任一整点为抄表时间,能储存12个月的历史电量。
　　■ 日历、计时和闰年自动切换。
　　■ 能按用户要求显示日期、时间、费率、电量等各种参数。

　　适用范围：

　　■ 220V 5(20)A----10(100)A为直接接入式仪表，适用于实施分时计价的城、乡居民照明计费用表。

DDSF879 Static Single-phase Multi-rate Watt-hour Meter (Double-counter/LED/LCD /LCD with PLC)
Main Features
■ Adopting special filtering network with strong anti-jamming ability
■ Adopting most advanced measurement chip, high-accuracy CPU, RTC and displayer
■ Manufactured with advanced SMT process
■ Measuring energy in different time segments respectively with 12 time segments and four tariffs (sharp/peak/ shoulder/off peak) programmable
■ Excellent anti- tamper & fraud function
■ Reliable function, high precision, high overload, Low self-consumption, light weight
■ Setting time segment, clock, passwords and other information by special programming device through RS485 or infrared interface.
■ Read all kinds of information except passwords by special reader and check the time when legally authorized
■ Distance of infrared communication can be more than 4 meters and communication angle be more than 15°
■ The reader can transfer the data to a computer
■ EIA-RS 485 interface can be added as per user.
■ The PLC meter with LCD have the function of PLC reading and remote load management
■ With RS485 and infrared communication interface whose communication protocol meeting DL/T645-1997 on multi-function Watt-hour meter communication protocol
■ Meeting standard GB/T17215-2002 (IEC61036: 2000) on “Alternating current static Watt-hour meters for active energy (classes 1 and 2)”,GB/T on particular requirement for multi-rate electricity meters and DL/T 614-1997 on multi-function Watt-hour meter
■Passed JQAC certificate according to GB/T19001 (ISO9001) Structure
■ With sealed case of flame-retardant、rust-proof and anti-aging
■ With RS485 and infrared communication interfaces.
■ Red LED indicating power pulse and flashing once per pulse
■ One channel of optical pulse output for calibration with width of about 80ms
■ Long-life & super-bright LED indicating time segments
■ Under normal conditions, the life of displayer( register、LED or LCD can be selected) is more than 10 years.
■ Working power supply is isolated by transformer
■ With program control switch within the meter
■ Having energy pulse output interface and RS484 interface on terminal block.
Technical Parameters
■ Rated Voltage(V) : 220，230
■ Operation Voltage (v): 70%Un~120%Un
■ Rated Current (A): 5(20), 5(30), 5(50), 10(40), 10(60), 15(60), 15(90), 20(80), 10(100)
■ Rated Frequency(Hz):50，60
■ Accuracy: class1, class2
■ Power Consumption: voltage circuit:≤2W/10VA; current circuit:≤1VA
■ Ambient Temperature(℃): -25~+55，limits of temperature(℃)：-45~+70
■ Relative Humidity:≤75%（annual average）
■ Tariff Selection: two/three/four tariffs ; time Segment:≥8
■ Accuracy of Clock: 0.5s/d(23℃)and variation with respects to temperature is better than 0.1s/(d·℃)
■ Capability of Battery: ≥1Ah(keep clock working for more than 10 years)
■ Size(mm):（LCD/LED）；（double- counter）
■ Life(year):＞10
Function
■ Measuring positive & negative active energy with negative energy accumulated into positive energy
■ Separately accumulating and storing the energy of each tariff (sharp/peak/ shoulder/off peak of the power)
■ Read automatically at any integral time of day in a month and can store total energy of 12 months
■ Able to show calendar, check time and make automatic adjustment in leap year
■ Displaying date, time, tariff, energy quantity and other parameters as per customers
Scope of Use
■ 220V 5(20) A----10 (100)A is for direct connected meters suitable for residential energy measurement (energy charged by multi-tariff) at urban or rural areas.