DJSF866 Single phase electronic DC energy meter

Overview

• The DJSF866 electronic single-phase multi rate DC energy meter is a new generation of intelligent high-tech energy metering product developed and produced by our company. It is based on dedicated metering chip technology and adopts the latest integrated circuit technology. It is designed and manufactured according to relevant international (IEC) standards for electric energy meters and China's power standards DL/T614-2007 "Multi functional Electric Energy Meter", DL/T645-2007 "Multi functional Electric Energy Meter Communication Protocol", JJG 842-1993 "DC Electric Energy Meter Verification Regulations", etc. It integrates measurement, monitoring, alarm, display, freezing, RS485 communication, and infrared communication functions, realizing DC measurement of charging piles and collection and storage of electricity information.

Technical parameters and working principle

• Technical Specifications

  model	DJSF866
  accuracy class	Level 1.0/2.0
  Auxiliary power supply voltage	～220V±30%
  Auxiliary power consumption	＜1.5W/10VA
  Rated voltage DC	400V/600V
  Calibration current DC (direct access type)	20A、40A、60A、80A
  Calibrated current DC (with external shunt)	100A、120A、200A、300A、400A、500A、600A
  Rated voltage of external shunt	75mV
  External splitter level	Level 0.5
  Operating Temperature	-25～60℃
  Extreme working temperature	-40～70℃
  relative humidity	Annual average<75%
  	30 days (within a year, these days are naturally distributed) 95%
  	85% in other occasional weather conditions
  starting current	0.001Ib
  MTBF	≥5′104h
  design life	15 years

  Note: Special specifications can be customized; Due to manufacturing issues with accessories, all products currently produced are of the external splitter type

  
  

• working principle

  The circuit metering part adopts dedicated metering chips, which can accurately measure active energy. It has the characteristics of high reliability, high precision, and low power consumption. The energy meter is powered by a transformer. The metering chip converts electrical energy into pulses, which are then collected and accumulated by the CPU chip. It also performs functions such as infrared meter reading, 485 meter reading, and LCD display. The clock adopts an external professional temperature compensation chip to ensure that the daily clock error is less than 0.5S/d at the nominal temperature, and the monthly error does not exceed 25 seconds. Far infrared communication uses 38kHz modulation, with a communication distance of no less than 5 meters. Redundant design is adopted for data security, with multiple backups to ensure the reliability of measurement data.

  The product principle diagram is as follows:

  

Basic functions

1. Electricity metering

• a) It has the function of measuring positive and negative active energy, and can set the combined active energy based on this.

• b) It has a time-sharing metering function, and active electrical energy can be accumulated and stored according to the corresponding time period rates; And save all current electricity data.

• c) It can store electricity data for the current month, the previous month, the previous month, the previous month, and the previous month. The settlement time can be set to any hourly time on any day of the month, and the electricity settlement date can be set from the 1st to the 28th of each month.

2. Remote cost control (optional)

• a) Under the premise of ensuring safety, the electrical parameters in the energy meter can be set through virtual media.

• b) Security authentication encryption requirements: When setting parameters, reading ESAM data, and issuing remote control commands to the electric energy meter through virtual media, strict password verification or ESAM module security authentication is required to ensure secure and reliable data transmission. The encryption algorithm of ESAM module complies with the relevant policies of national password management and uses SM1 algorithm.

3. Measurement and monitoring

• It can measure voltage, current, active power, etc. The measurement error (citation error) shall not exceed ± 1%.

4. Event record

• a) Permanently record the occurrence time of the reset event on the energy meter and the energy data at the time of reset.

• b) Record the total number of programming attempts, the time of the last 10 programming attempts, operator code, and data identification of programming items.

• c) Record the total number of calibration times (excluding broadcast calibration), the time of the last 10 calibration times, and the operator code.

• d) Record the total number of power outages, as well as the last 10 instances of power outages occurring and ending.

• e) Record the total number of times the watch cover has been opened, as well as the occurrence and end times of the last 10 watch cover opening events.

5. Rate and Time Period

• a) Adopting a built-in hardware clock circuit with temperature compensation function, it has calendar, timing, and leap year automatic switching functions. The output frequency of the internal clock terminal is 1Hz.

• b) It has 2 sets of time zone tables and can be configured with 2 sets of time zone table switching times;

• d) It has 2 sets of daily time slot tables and can be configured with 2 sets of daily time slot table switching times;

• d) Public holiday periods can be configured.

• e) You can configure the weekend and the time slot table number for selecting weekends.

6. Data freeze

• a) The data freezing methods include timed freezing, instantaneous freezing, daily freezing, agreed freezing, and hourly freezing.

• b) Each freezing method can be frozen by selecting the data type through the corresponding freezing data mode word, and can choose forward active energy, reverse active energy, variables, etc.

• c) Timed Freeze: Configure the timed freeze time, freeze on a monthly, daily, or hourly basis, and save the most recent 60 frozen data.

• d) Instant Freeze: Under abnormal circumstances, issue an instant freeze command to freeze instantly, which can save the last 3 frozen data.

• e) Daily freeze: Configure the daily freeze time, which can save the frozen data of the last 2 months.

• f) Agreed freeze: Freeze the electrical energy and other important data at the time of conversion when switching between two sets of time zone tables, switching between two sets of daily time zone tables, or when the power company deems it necessary. Can save the last 2 frozen data switches.

• g) Whole hour freeze: Configure the start time and interval time for whole hour freeze, and can save the last 254 frozen data.

7. Communication

• a) The electric energy meter has one infrared communication interface and one RS485 communication interface. The physical layers of infrared and RS485 communication interfaces are independent of each other, and the damage of one communication interface does not affect the normal operation of other communication interfaces. In addition, photoelectric isolation is implemented for communication interfaces and internal circuits of energy meters, with failure protection circuits.

• b) The communication baud rate can be set, with standard rates of 1200bps, 2400bps, 4800bps, and 9600bps; The default baud rate for RS485 interface is 2400bps; The default baud rate for modulated infrared communication interfaces is 1200bps.

• c) The communication protocol of the electric energy meter complies with the requirements of DL/T645-2007 and its filing documents.

8. Power outage

• After a power outage, the electricity meter can be awakened by pressing the button. If there is no button operation after the electricity meter is awakened, it will automatically cycle and display once before returning to the power-off state. If there is a button operation, it will return to the power-off state after 30 seconds of button operation.

9. LED indication, pulse signal output

• a) The electric meter panel is equipped with LED indicator lights for active power pulses. The power pulse constant is related to the meter specifications, and the specific values can be found on the meter nameplate.

• b) The auxiliary terminals of the electric meter are equipped with active calibration pulse signals and multifunctional testing signals.

• c) Multi functional testing interface: The multifunctional testing interface of the auxiliary terminal of the electric energy meter can output daily timing error detection signals and time period switching signals. The two output signals use the same output interface and can be switched through programming settings. After the power meter is powered off and then powered on again, the output signal of the multifunctional testing interface defaults to the daily timing error detection signal.

10. Electricity meter sleep mode

• When the external AC power supply is cut off, the electricity meter is powered by the internal battery to maintain uninterrupted operation, and at the same time, the electricity meter automatically enters a sleep state to reduce battery power consumption; When the external AC power supply is restored, the electricity meter exits sleep mode. Can be awakened in sleep mode.

11. LCD display

• 11.1 Use a large LCD screen to display battery level and parameters, which is intuitive and clear, and convenient for meter reading. The LCD adopts FSTN material with a temperature range of (-25~+80) ℃, and the liquid crystal polarizer has UV protection function. Display various parameter settings and measured electricity data on the LCD through button operations. Automatically restore the loop display mode after stopping button operation for 60 seconds.

• 11.2 It has two display modes: automatic loop display and button display. When using automatic loop display, the loop display time can be set (5-20 seconds), and the display content can be set through programming.

• 11.3 After the external power supply loses power, the environmentally friendly column lithium battery supports LCD power-off wake-up display.

• 11.4 After a power outage, the LCD display will automatically turn off; After the LCD display is turned off, the LCD display can be awakened by pressing the button, and the backlight will not light up during the wake-up period. If there is no operation after key wake-up, the LCD will be turned off 30 seconds after the end of the key operation.

• When the instrument is powered on, the LCD backlight wake-up methods include button wake-up and infrared wake-up (any infrared device can be woken up).

• The 11.6 instrument will display a full screen self-test for 5-20 seconds when powered on.

  

  
  

• 11.7 Main LCD display interface:

• Full screen display interface

  

  
  

• 11.8 Display items with corresponding Chinese or symbol displays. Please refer to Table 1-1 for details:

  Table 1-1: Description of LCD graphics and symbols:

  LCD graphics	Instructions
  	1) Current, previous month/time - previous December/time electricity consumption, cumulative, combined, positive/negative, total, peak, average, and valley electricity consumption 2) Remaining amount, constant 3) Step by step electricity price, electricity consumption (unused) 4) Overdraft amount (unused) 5) Time, time period, table number
  	Data display and corresponding unit symbols
  	1) Infrared and 485 communication 2）Display as test key status, not as official key status 3) Hanging indication of electric energy meter 4) In module communication 5) Reverse power indication 6) Battery undervoltage indication 7) Effective indication of infrared authentication 8) Phase line, neutral line
  	1) IC card 'reading' prompt 2) IC card reading "successful" prompt (not used) 3) IC card reading 'failed' prompt (unused) 4) Flashing when the remaining amount of the 'purchase electricity' is too low 5) Relay tripping status indication 6) Overdraft status indicator (unused) 7) Status indication (hoarding) when the IC card amount exceeds the maximum stored value (unused)
  	1) Indicate the current electricity prices for the 1st, 2nd, 3rd, and 4th tiers of operation 2) Indicate the current rate status (peak to valley) 3）“ ”Indicate the current and backup tiered electricity prices,Indicates running on the current ladder,Indicates the ladder to be switched, i.e. the standby ladder rate is effective. 4) ①② represents the rates for the first and second time periods/current and backup time periods, with the default being the time period

  
  

Appearance and installation dimensions

(For reference only, subject to the actual product)

wiring diagram

(For reference only, subject to actual conditions)

Outline structure diagram and dimension table of external splitter

Note: When installing the external shunt, it needs to be connected in series at the "V+" position of the device. The two output leads "I+" and "I -" of the shunt should be connected to terminals 1 and 2 of the electricity meter in the order shown in the diagram. The factory default is the external splitter access method.

Precautions

• The voltage must be strictly connected according to the voltage and current levels indicated on the label.

• During installation, the wiring should be tightened and the meter should be securely hung on a sturdy, fire-resistant, and vibration resistant screen. It should be installed vertically.

• After wiring, the end cap should be sealed with lead, and it is recommended to add lead seal to the top cover of the meter.

• The meter should be stored in an environment with a temperature of -40 to 70 ℃ and a humidity of less than 85%, and should be placed in its original packaging with a stacking height of no more than 5 layers. Electric meters should not be stored after unpacking.