DDS228 Single-phase electronic energy meter (LCD display with RS-485 remote opening and closing)

Overview

• The DDS228 single-phase electronic energy meter (hereinafter referred to as the "instrument") is an energy meter used to measure single-phase active energy with a reference frequency of 50Hz. This instrument is a high-tech product manufactured using internationally advanced ultra-low power large-scale integrated circuit technology and SMT process. It has significant advantages such as high measurement accuracy, good stability, high reliability, intuitive display, and strong overload capacity. The key components are selected from internationally renowned brands of long-life devices, which improves the reliability and service life of the product. The data display adopts LCD, which is intuitive and has infrared communication, making it convenient for users to manage energy data. This instrument complies with the GB/T 17215.321-2008 standard and supports communication with DL/T 645-1997/2007 and ModBus protocol (optional wireless 4G communication).

working principle

• As shown in the figure below, the main working principle of this instrument is that the electricity consumed by the user is sampled through current and voltage; After A/D conversion, it is sent to the multiplier for multiplication, and the multiplied signal is then converted by the D/F converter. The pulse output by the frequency division circuit is sent to the microcontroller CPU for data processing and measurement. The microcontroller CPU displays the electrical energy data through LCD and reads the electrical energy data through 485 and infrared interfaces.

  

Model and specifications

Main technical parameters

• The basic errors are shown in the table below:

  current value	Power factor COS Φ	Error (%)
  		Level 1	Level 2
  0.05Ib≤I<0.1Ib	one	±1.5	±2.5
  0.1Ib≤I≤Imax	one	±1.0	±2.0
  0.1Ib≤I<0.2Ib	0.5L	±1.5	±2.5
  	0.8C	±1.5	—
  0.2Ib≤I≤Imax	0.5L	±1.0	±2.0
  	0.8C	±1.0	—

• Starting current (power factor COS Φ=1)  0) :  < 0. 004Ib (Level 1),<0.005Ib (Level 2).

• Stealth: When the voltage line is applied with 115% Un and there is no current in the current circuit, the output pulse of the energy meter shall not exceed one.

• Power consumption: Voltage line power consumption ≤ 1W/8VA, current line power consumption ≤ 1VA; voltage line power consumption ≤ 3W/12VA in communication state.

• Working power supply voltage: 0  9Un～1. 1Un。

• Designated temperature: -25 ℃ to+60 ℃; Extreme working temperature: -40 ℃~+70 ℃, relative humidity: annual average ≤ 75%.

Main functions

• Total active energy metering function.

• The LCD displays the electricity consumption with 6 integers and 2 decimals.

• Verify pulse output

• Supports infrared communication and 485 communication, wireless 4G communication (optional).

• The communication baud rate is fixed at 1200BPS (97/07); 9600 (ModBus).

• Support remote opening and closing function (optional).

Outline drawing and installation instructions

• Outline drawing

  
  

• Wiring diagram (for reference only)

  Connect the wires correctly according to the reverse side of the terminal box cover, as shown in the wiring diagram:

  

• This product is a solid-state static instrument with no user adjustable components inside, and there is no need to open the casing during use.

• The instrument is inspected and sealed with lead before leaving the factory. Before installation and use, users must check the qualified mark and ensure that the lead seal is intact before installation and use. For instruments without lead seals or stored for too long, relevant departments should be asked to re inspect them. Only those that pass the inspection can be installed and used.

• The instrument should be installed in a well ventilated and dry indoor area, fixed with three screws. When installing, holes should be drilled on the bottom plate first, and the base should be fixed on a sturdy, fire-resistant, and non vibrating object. The installation height should be about 1.8m to ensure safe and reliable installation and use. In places with pollution or potential damage to the instrument, it should be protected. The instrument should be wired correctly according to the wiring diagram. It is recommended to use copper wire or copper joint for the incoming wire of the terminal box. The screws inside the terminal box should be tightened to avoid burning due to poor contact and heat generation.

• The instrument will enter normal operation after being powered on with the correct wiring as described above.

• If any abnormal phenomena are found during the use of the instrument, it cannot be dismantled without authorization. Qualified professionals should be hired to handle it.

Transportation and storage

• Instruments must be transported and stored in their original packaging conditions. Instruments should be installed indoors as much as possible, and dedicated instrument boxes must be used for protection when installed outdoors. There should be no corrosive gases present in the storage environment, and the storage height should not exceed five layers.

• Instruments should not be subjected to severe impacts during transportation and unpacking, and should be transported and stored in accordance with the provisions of JB/T9329-1999 "Basic Environmental Conditions and Test Methods for Transport and Storage of Instruments and Meters".