Model DTSD31/32, DSSD31/32 Electronic Three-phase Multi-function Watt-hour Meter is a hi-tech intelligent energy-measuring instrument integrating patented high & new technology of Shenzhen Star Instrument Co., Ltd. This kind of meter adopts large-scale IC circuit, FRAM (ferro-electric memory technology), RS485/RS232 communication ports with isolation, infrared communication port, LCD display with large screen and wide temperature scope, real-time clock chip, electromagnetic compatibility (EMC) and advanced SMT electronic components assembling technique. Based on fully consideration of user's power-consuming status and the EMC of power equipment, this new energy-measuring instrument is elaborately designed and manufactured in accordance with IEC standards, national standards and ISO9001 quality assurance system. This meter series combines various functions into one form to realize (1) measuring & displaying three-phase apparent power, active energy (double direction) and reactive energy (four phases); (2)measuring power energy and demand at different intervals according to relevant rates and dealing with data; (3) measuring and displaying electrical parameters such as real-time power, power factor, voltage, current and frequency etc; (4) transferring data related to load and power-consuming parameters curve to distant terminal; (5) recording, alarming and displaying voltage loss. Therefore, this meter can in time satisfy user's requirement on the power modernization management effectively and is a special measuring instrument that matches the modernization management. Additionally, the meter can be widely applied to power plant, power supply station and distribution station, measuring ports, and power comprehensive statistics and management of enterprises & government units. Features: We design the circuit, select components, solder, assemble, calibrate and test the meter on fully consideration of environment difference, meter's EMC and life expectancy. So the meter's long-term operation stability and measuring accuracy are guaranteed and its measuring accuracy is not subject to the change of time, frequency, and temperature and voltage etc. This meter has small size, light weight, perfect sealing and polished appearance. The meter is equipped with reserve Lithium battery for meter reading when power failure happens so that meter reading can still be processed at power failure without external battery input. This meter reading model won't affect the storage of meter data and life expectancy of real-time clock. The relevant operation data of meter can be transferred through palm computer (infrared) or RS485/RS232 port. As ferro-electric memory technology and special Lithium battery are adopted in this meter as an alternative power for real-time clock, it can fully guaranty the accuracy and credibility of data that the meter has set, measured and recorded when power failure happens in power network; meanwhile the calendar clock and interval program control function can keep running normally. After the power supply is resumed, the meter will restart its routine operation automatically. Output ports of photoelectric coupling for active, reactive, and clock impulse are set on the meter terminal box for error testing or data collecting, also there are 2 relay output ports for load control. The meter adopts multi-phase power supplying circuit to guarantee its normal operation at phase missing. And the accuracy of meter measuring won't be affected under unbalanced voltage or load. The meter is available for the area with environmental temperature ranges from 25 ~65 and relative humidity below 90%. Function: A. Energy Measurement 1. Measuring and displaying energy amount of forward active, reverse active, four-quadrant reactive at sharp, peak, shoulder & off-peak levels and accumulative total energy amount up to data and in last two months. 2. Measuring and displaying accumulative total energy amount & the amount at sharp, peak, shoulder & off-peak levels of forward reactive (+RL, +RC), reverse reactive (-RL, -RC), up to date and in last two months. 3. The energy measuring value is 8-digit display with 6 integers and 2 decimals. Measurement units for apparent, active and reactive energy are expressed respectively as kVAh, kWh, kvarh. B. Demand Measurement 1.Recording and displaying Max Demand together with its date & time of forward active, reverse active, four-quadrant reactive, forward reactive(+RL, +RC) and reverse reactive (-RL, -RC) in this month and last two months. 2.Recording and displaying Max Demand together with its date & time of forward active, reverse active, four-quadrant reactive, forward reactive and reverse reactive at sharp, peak, shoulder and off-peak levels in this month and last two months. 3.When the meter runs to the preset of meter-reading, the Max Demand will be reset after automatic meter reading, meanwhile this can also be done manually by authorized person and recording the data & time of manual reset. 4.The demand measurement unit is 6-digit display with 2 integers and 4 decimals. Measurement unit for active and reactive is respectively kW, kvarh. C. Operation Record Function 1. Recording and displaying the date & time of last 1-10 times of programming, for instance, modifying the operation parameters such as rate and interval etc. 2. Recording and displaying the date & time of last 1-10 times of Max Demand resetting including manual operation and infrared operation. 3. Recording and displaying the date & time of last 1-10 times of initialization resetting carried out by authorized person. D. Function of Voltage Loss Warning, Display and Record 1. When the phase current I>=0.5%Ib, if any phase voltage loss or reduce less than 70%Un+-2V, the meter decides it as fault voltage loss, then gives off acoustic-optic warning and displays the fault phase. If the fault voltage loss lasts over 1minute, the meter will start its internal voltage loss recording program to file the following data into relevant voltage loss record of each phase: the date and time that voltage loss happens and ends, the energy (Ampere hour) occurring during the fault, times and accumulative time of voltage loss. (Note: each phase keeps the data of last 1-10 times of voltage loss). When voltage resumes up to 75%Un+-2V,the meter will cancel the voltage loss warning and restores its normal display. 2. When voltage loss happens on all three phases and the voltage reduce less than 60% Un+-2V, there is no display in the meter. E. Function of Overload Warning and Trip (Optional) The meter has the function of presetting overload warning and trip. When three-phase active/reactive load exceeds the warning or trip value preset, the meter responds by warning overload/relay tripping and send out warning/trip signal so that the user cab fulfill load control. F. Record Function of Load Curve 1. The meter has the function of recording load curve with 30minutes interval for 84days through its 3 channels. 2. The load curve data can be transmitted through RS485/RS232 port to its upper management system and be used to draw load-curve in order to manage power consuming more properly. G. Function of Remote Programming and Meter-reading Upon user's requirement, the power management department can adopt the standard RS485/RS232 port and power energy impulse output of our three-phase electronic multi-function watt-hour meter to form a remote meter reading management system through load control terminal or relevant transmission manner to realize the remote control functions of power management department such meter reading, load control etc. H. Function of Meter Reading at Power Failure When the standby battery for meter reading at power failure works normally, the user can check the operation parameters by pressing the meter's scroll display key and can also realize meter reading at power failure. Technical Standards: Rating frequency: 50Hz/60Hz