Overview
The product adopts the precise and reliable active/reactive bi-directional power-measuring chip, plus the advanced microprocessor for data processing, communication and display to support 3-phase forward/backward multi-rate watt-hour measurement, 3-phrase reactive four-quadrant multi-rate watt-hour measurement, 3-phase forward/backward multi-rate maximum-demand measurement, 3-phase reactive four-quadrant maximum demand measurement, measurement of 3-phase current, 3-phase voltage, 3-phase power, reactive power and power factors, phase failure record, and far infrared meter reading as well as RS-485 bus remote data communication. This meter can be used as the gateway meters of the power plant and the transformer station, and is widely applied in the bus balance meter, power transmission feeder line meter, measuring and monitoring instrument of power distribution or transformation, and onsite meters. The product performance is in conformity with the stipulations of DL/T614-1997 - Multi-function Watt-hour Meter and DL/T645-1997 - Communication Protocol for Multi-function Watt-hour Meter.

Functional characteristics:

＊Watt-hour measuring function With the digital measuring chip, this product has realized the digital check of the metering accuracy; and with the variable gain measurement and multi-section digital compensation, it has also realized the four-rate forward/backward and reactive four-quadrant power demand measurement of high overload times.

＊Demand indicating function This product supports the forward/backward and reactive four-quadrant four-rate demand counting function, and simultaneous recording of the generation time of each demand data. Moreover, it provides two counting modes such as interval mode and sliding difference mode.

＊Voltage, current and power factors indicating function The splitphase voltage, current, power factors and total power factors can be directly displayed on the LED screen.

＊Automatic meter reading function This product has the function of automatic meter reading based on period of one month or one week, and supports the electric quantity storing processing and demand resetting.

＊Data logging This product supports up to16 times of automatically electric quantity and demand historical data.

＊Load curve recording This product can record the active power, power, reactive power, power, 3-phase voltage, current and load curve of power factor as required and the recording interval can be preset.

＊Power consumption fixing/freezing function This product has the power consumption data fixing/freezing function to meet the requirements of the performance index appraisal of the transformer station.

＊Power off time recording This product supports 64 times of the recording of “Month, Day, Hour and Minutes” of power off and on.

＊Phase failure data and time recording This product supports 7 times of separate recording and storing of 3-phase phase failure accumulating times, accumulated times of phase failures that don’t clear upon the Reset command, accumulated time, accumulated forward/backward active power consumption during phase failure. In addition, this product supports the recording of the phase failure times, times and forward/backward active power consumption during one-phase failure and two-phase failure. This product also supports the recording of the current values of the total active or reactive forward/backward power consumption at the beginning or ending of phase failure (the last 8 times).

＊Voltage loss data and time recording This product support 7 times of separate recording and storing of the accumulated times and time of 3-phase voltage loss that doesn’t clear upon the reset command, and forward/backward accumulated active power consumption during the period of voltage loss. Additionally, this product also supports the recording of the current value of the total active or reactive forward/backward power consumption at the beginning and ending of voltage loss (the last 8 times).

＊Current loss data and time recording This product supports the recording of the accumulated time, times, beginning and time of current loss of each phase.

＊Current unbalance recording This product supports the recording of the accumulated time, times, and beginning and ending time of current unbalance of each phase.

＊Voltage qualification rate, overvoltage and undervoltage recording This product supports the recording of total running time of each phase, the running time of each phase when the voltage is beyond the upper/lower limit (default: 20%), and the starting and ending time of overvoltage and undervoltage (default: 30%).

＊Data display The power consumption and demand data can be displayed through LED screen, and the LED screen is a “Graphics Dot Matrix Segment Composite Screen”, and with the dot matrix Chinese hint, the data display is more visualized. ABC 3-phase voltage, current, power factors and total power factors can be displayed at real time; and the display content and mode can be programmed at will.

＊Auxiliary power supply This product can provide auxiliary power supply interface suitable for remote meter reading when power is off.

＊Input/output interface This product supports 4-circuit pulse output with optical Isolation, RS485, second signal pulse output, infrared remote control display, interfaces for programming and meter reading.

＊Housing: Polycarbonate material integrated structure, high temperature resistant, moisture proof, durable, and high mechanical strength. Main technical indicators

＊Voltage circuit power consumption: ≤1W 1.5VA（3×100V）, 2W 3.5VA（3×220V）.

＊Width of power pulse output isolated remotely and dynamically : 80（1±20%）mS

＊Basic baud rate of data communication: 1200bps, and 2400, 4800 and 9600bps (optional)

＊Daily time recording error : ≤0.5S/d.

＊Error of rate and time-interval switch: ≤0.1S.

＊Operating temperature: Normal operating temperature shall be -10℃～+45℃.

＊Ultimate operating temperature: -25℃～+70℃.

＊The environment humidity : up to 85%.

＊Electromagnetic compatibility :The meter can bear 8kV electrostatic discharge, 27 - 450MHz high frequency electromagnetic field and the interference from 4kV electrical fast transient pulse group.

＊Backup battery: Continuous power-supply time > 6 years. 

 Models and specifications

Model	Class		Display	Voltage specifications	Current specifications
	Active	Reactive
DSSD2828	0.2S	1.0S	LCD	3×100V	3×1.5(6)A
DSSD2828	0.5S	2.0		3×100V	3×1.5(6)A
DSSD2828	0.5	2.0		3×100V	3×1.5(6)A
DSSD2828	1.0	2.0		3×100V	3×1.5(6)A