DTU 2000 Series

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Functions

DTU 2000 series is generally installed at on-site power stations to apply the monitor and control of signal performance. DTU 2000 series is designed in multiple processor technique. Each I / O Card has its own processor that is responsible for the basic data acquisition function. The basic functions are as follows.

  • Data Acquisition Processing
    • DTU acquires digital and analog signal from station plus processing and storage in the memory and ready to transmit the data back to communication server or control center.
  • Sequence of Event Report
    • DTU provides the SOE function (Sequence of Event) to monitor the status and sequence, or any changes of equipments at the station. An event is defined as a single change of state. Each time an event is detected, RTU will time tag the event and save a description of the event and the time tag in a first in first out (FIFO) buffer. There is 1024 events buffer in DTU.
  • Control Output
    • Two types of control command can be transmitted from the Master Station to devices in the power system via the DTU. One is Trip / Close command, the other is Direct Set point command.
    There are two types of control output using Trip / Close command. One is ON / OFF operation output to control CBs, ABSs and the other is Regulation operation output (Raise / Lower) to control the position of transformer taps. Two types of Trip / Close commands are supported.
  • Communication Function
    • The communication function of DTU can be divided into internal communication and external communication.
    • SCADA Master: CDC Type II, DNP3.0, IEC 870-5, CDT (China).
    • DTU Sub-Master: Modbus RTU, DNP3.0, IEC 870-5.
    • IED: Modbus RTU, DNP3.0.
  • Self-Diagnostic Function
    • DTU is designed with self-diagnostic function. Every abnormal status of DTU is recorded as System Event, or indicated by LED excitation on the panel. The System Event record can be retrieved by test set and store in its hard disk, which is very easy to detect errors in maintenance.
  • Programmable Algorithm Function
    • DTU have the capability of user definable "Sequential Algorithm". The "Sequential Algorithm" within DTU can communicate through a common variable database which consists of analog inputs, digital inputs, accumulator inputs, pseudo points, alarm (system) status, digital output, and system clock.
Hardware Structure

DTU hardware structure is designed as a plug-in type set up in a 19" rack. The plug-in type configuration is ideal for maintenance and expansion. The dimension of the card is followed by the European standard of 100 mm * 160 mm. DTU is consists of 4 units.

  • Power Supply Unit
    • The power supply of DTU contains the following cards:
    • DC 24V / DC 5V & 24V PS Card
    • AC 220V / DC 5V & 24V PS Card
  • Main Unit
    • The main unit of DTU consists of 1 Back plane and 1 Master CPU card. The I / O CPU and CM cards can install if needed for the system.
    • Back plane
    • CPU Card / CM Card
    • U96 card
  • I / O Interface Unit
    • DTU provides various types of I / O interface card, which correspond the system requirements in a station. I / O card can divided in different functions of input and output to monitor and to study the status of operation in stations. The detailed description is follows:
    • DI Card
    • ACC Card
    • DO Card
    • DOH Card
    • AI Card
    • AI Card ( HS )
    • AO Card
  • Intelligent Power Meter module
    • HC 6730 power meter is designed with high precision intelligent of digital power and energy transducer, which can measure input signals from 3 CT and 3 PT simultaneously. HC 6730 can measure more than 90 power parameters and able to retrieve plus demonstrate different parameters on the display. In the communication interface, HC 6730 can preset the parameters in the provided PCTool user's manual.