DTSF866/DSSF866 Three phase electronic multi rate active energy meter (Liquid display peak flat valley)

Overview

• The DTSF866/DSSF866 three-phase electronic multi rate energy meter is designed using advanced energy metering chips combined with mature multi rate technology. It applies digital sampling processing technology and SMT technology, and is designed and manufactured according to the actual electricity consumption of residents. It is an internationally advanced level of energy meter. This meter implements time-sharing measurement, sets daily automatic data transfer, programs and reads meters on handheld terminals or PCs, and displays on LCD screens. This meter can be set with 4 rates, 10 time periods, 4 time zones, and a 12 digit meter number, and has the functions of power testing pulse output and maximum demand. The performance indicators of this meter comply with GB/T 17215.321-2008 "Level 1 and Level 2 Static AC Active Energy Meters", GB/T 15284-2002 "Special Requirements for Multi Rate Energy Meters", and the communication protocol complies with the requirements of DL/T645-1997 "Communication Protocol for Multifunctional Energy Meters" and special protocols required by users (such as Modbus protocol, please contact the manufacturer's technical personnel if a register point meter is needed).

working principle

• The working principle of the electric energy metering unit in this instrument is that the core of the electric energy metering unit is the metering chip. The current of each phase of the measured electrical energy is sampled by a transformer to obtain a voltage signal, which is then amplified by the differential amplifier circuit inside the measuring chip. The amplified signal is converted into a digital signal proportional to it through A/D conversion, and after high pass filtering to remove the DC component in the signal, it enters one input terminal of the digital multiplier. The voltage signal of the measured electrical energy is sampled through resistance voltage division, amplified by the differential amplifier circuit inside the measuring chip, and then converted into a digital signal proportional to it through A/D. It enters the other input terminal of the digital multiplier and multiplies with the signal of the current channel to complete the instantaneous power measurement of the measured electrical energy. The instantaneous power output of each phase is integrated through a digital low-pass filter, and then the absolute value is accumulated before entering the "digital/frequency" converter. The pulses output by the frequency divider circuit are isolated and sent to the CPU unit for processing.

• The working principle of the CPU unit is that the high-frequency pulses output by the energy metering unit are used as passive pulses through a photoelectric coupler for factory inspection and user verification of the energy meter; Another route is sent to the CPU chip for data processing. Under the instructions of the system (energy meter program), the CPU calculates the active power value based on the memory and instrument constants in the data storage, and then transfers it to the internal memory. The stored data can be displayed through LCD or output through infrared and RS485 communication methods.

Model and specifications

Main technical parameters

• The basic error is shown in the following table: (with balanced load percentage error limit)

  current value		Active Level 1.0
  Directly connected to the instrument panel	Transformer instrument	Power factor COS Φ	Error%
  0.05Ib≤I<0.1Ib0.1ib<	0.02Ib≤I<0.05Ib0.05ib<	one	±1.5
  0.1Ib≤I≤Imax	0.05Ib≤I≤Imax	one	±1.0
  0.1Ib≤I<0.2Ib0.2ib<	0.05Ib≤I<0.1Ib0.1ib<	0.5L	±1.5
  		0.8C	±1.5
  0.2Ib≤I≤Imax	0.1Ib≤I≤Imax	0.5L	±1.0
  		0.8C	±1.0

  Error limit with unbalanced load percentage: ± 2.0% for active level 1.0 meter.
  

  
  

• Starting current

  Connected through a current transformer: the active 1.0 level meter is 0.002Ib, directly connected: the active 1.0 level meter is 0.004Ib

  
  

• Stealth

  When the voltage circuit is 115% of the rated voltage and the current circuit has no current, the test output of the energy meter should not generate more than one pulse.

  
  

• Working voltage range

  Normal operating voltage: 0.9-1.1 rated voltage

  Maximum operating voltage: 0.7-1.2 rated voltage

  
  

• Power consumption: Voltage circuit power consumption ≤ 1.5W/5VA, current circuit power consumption ≤ 2VA

  
  

• Environmental conditions: Standard working temperature is -25 ℃~+55 ℃, and the maximum working temperature is -40 ℃~+70 ℃. Annual average relative humidity: ≤ 75%

  
  

• Data retention validity period after power outage: ≥ 10 years

Function and Features

• Measurement function

  Measure positive active energy in a time-sharing manner (including negative energy in the positive direction) and store its data.

  Electric energy is accumulated and stored separately based on total, peak, flat, and valley values.

  Communication, time switching, repeated power outages, and power ups do not affect the accuracy of the energy meter's measurement.

  The electricity meter can store historical data from the previous 12 months. The freezing and transfer date for electric energy data is any designated day from the 1st to the 28th of each month at any hour.

  After power failure, all stored data will not be lost and can be maintained for more than 10 years.

  
  

• Multi rate function

  Four rates can be set, including peak, off peak, flat, and valley rates, for a period of 10 days. The minimum interval between time periods is 1 minute, and the time periods can cross zero. They are arranged in ascending order when set.

  The actual time and preset time of the start and end of any time period have an error of less than 5 seconds.

  The electric energy meter adopts a hardware clock circuit and has a temperature compensation circuit to ensure that the clock error is controlled within 30s/month under normal working conditions. The built-in clock has calendar, timing, and leap year automatic switching functions. The clock is powered by an independent lithium battery to maintain its operation after a power outage. The battery capacity is ≥ 1.0Ah, and the battery life is over 10 years, with a continuous working time of more than 3 years.

  It has the function of broadcasting and timing.

  
  

• display function

  Using a wide temperature and large LCD display to show various types of information; The number of digits displayed for electric energy is 6 for integers and 2 for decimals.

  It has automatic parameter rotation function, with a rotation time of 10 seconds and adjustable rotation item data, up to 45 items can be set.

  It has a power-off button rotation function, and the button rotation time is the same as the rotation time. If there is no button after 20 seconds, the LCD will automatically turn off.

  
  

  
  

• communication function

  Programming and meter reading can be completed through infrared communication or RS485 communication via handheld terminals or PCs.

  The RS485 interface is electrically isolated from the inside of the meter and is designed with lightning protection circuits.

  The communication protocol refers to DL/T645-1997 protocol.

  
  

• Output function

  Equipped with active pulse test port output function (meeting the requirements of remote pulse output, with a pulse width of 80ms ± 20ms).

  It has clock output function. When powered by mains electricity, the clock output terminal outputs a 1-second signal, which is optically isolated for detection purposes.

  It has RS485 output function and can achieve RS485 centralized meter reading.

  
  

• Event recording function

  It can record the total maximum active power demand for the current and last two months, as well as the time of occurrence.

  Last programming time and programming frequency

Installation and wiring methods

• The instrument shall be inspected and sealed with lead before leaving the factory. Before installation and use, it is necessary to check whether the lead seal is intact. If the lead seal is intact, it can be installed and used. For instruments without lead seals, relevant departments should be asked to re inspect them. Only after passing the inspection can they be installed and used.

• Electric energy meters can be installed indoors or outdoors, and the base plate for installing the meter should be fixed on a sturdy fire-resistant wall. There should be no corrosive gases in the air to ensure safe and reliable installation and use.

• The electric energy meter should be wired according to the wiring diagram on the junction box, and the screws inside the terminal box should be tightened to avoid burning due to poor contact.

• The electric energy meter should be properly wired and can enter normal operation after being powered on. If any abnormal phenomena are found during use, users should not disassemble it without authorization and should seek the assistance of qualified professionals for handling.

• Wiring diagram:

  

  
  

• Schematic diagram of pulse testing port:

  

  Internal optocoupler output of the table

  
  

• Outline and installation dimension diagram:
  

Transportation and Storage

• The transportation and unpacking of electric energy meters should not be subjected to severe impacts. They should be transported and stored in accordance with the provisions of JB/T 9329-1999 "Basic Environmental Conditions and Test Methods for Transportation, Storage and Transport of Instruments and Meters", and placed according to the requirements on the packaging box.

• The energy meter should be stored in its original packaging, with a storage environment temperature of -25 ℃ to+70 ℃, an average relative humidity not exceeding 75%, and no corrosive gases in the storage environment. It should be moisture-proof.

• Electric energy meters should be stored in the warehouse and placed on shelves with a stacking height of no more than 5 boxes. After unpacking, the stacking height of a single packaged electric energy meter should not exceed 10 pieces.

• Please do not power up the meter and contact the supplier as soon as possible if there are obvious signs of damage to the casing caused by severe impact or falling from a high altitude during transportation, retrieval, or installation.