ABB TSITU01 TSI Termination Unit

ABB TSITU01 TSI Termination Unit

Overview

Product Definition and Function: ABB TSITU01 TSI Termination Unit (TSI Termination Unit) is an important device for turbine supervisory instrumentation (TSI) in industrial automation systems. Its main function is to receive, process and transmit signals from various sensors related to the turbine, including those used to monitor shaft vibration, shaft displacement, speed and other parameters. Through this terminal unit, these sensor signals are converted into a format suitable for processing by the control system and transmitted to the upper control system, thus realising accurate monitoring and control of the turbine's operating status.

Working Principle

Signal reception:

Sensor Connections and Signal Types: the TSITU01 unit has several input interfaces for connecting various turbine sensors. For example, for shaft vibration sensors, usually accelerometers or proximity sensors, they output analogue electrical signals (e.g. voltage or current signals) related to the amplitude and frequency of shaft vibration; shaft displacement sensors output signals reflecting changes in the position of the shaft in the axial direction; and rotational speed sensors output pulsed signals with a frequency directly proportional to the rotational speed of the turbine.

Signal conditioning: When the sensor signals enter the terminal unit, they are first conditioned. For analogue signals, this includes filtering (removing high-frequency noise and interfering components from the signal), amplification (amplifying weak signals to a level suitable for subsequent processing) and level conversion (converting external signal levels to levels that can be processed within the unit). For example, a weak voltage signal from a shaft vibration sensor may need to be amplified to a suitable range for subsequent analogue-to-digital conversion (A/D) accuracy.

Signal processing and conversion:

A/D conversion (for analogue signals): The conditioned analogue signal is fed into the A/D converter circuit, which converts the continuous analogue signal into a discrete digital signal. The unit's A/D converter usually has a high resolution, e.g. 12 - 16 bits, which allows the analogue signal to be accurately quantised into digital values. The converted digital signals provide a more accurate representation of the physical quantities measured by the sensor, e.g. vibration amplitude, displacement, etc.

Digital signal processing (including pulse signals): For the pulse signals output by the speed sensor, the terminal unit processes them for counting, frequency measurement, etc. The digital signals are processed by the terminal unit. For example, the speed of the turbine is determined by counting the number of pulses per unit time. At the same time, for all digital signals (including converted analogue signals and raw pulse signals), operations such as data packing and adding timestamps are carried out so that these signals can be accurately identified and processed during transmission.

Signal transmission:

Communication protocols and interfaces: the processed signals are transmitted to the upper control system via communication interfaces. tsitu01 supports a wide range of industrial communication protocols, such as Profibus - DP, Modbus, etc. These protocols ensure that the signals can be transmitted to the upper control system from different locations. These protocols ensure that signals can be transmitted stably and quickly in different industrial network environments. For example, under the Profibus - DP protocol, signals can be transmitted to the control system in a defined format and at a defined rate (e.g. up to 12 Mbps).

Data transmission integrity guarantee: During transmission, checksums and retransmission mechanisms are used to ensure data integrity. For example, a Cyclic Redundancy Check (CRC) code is added, which allows the receiver to verify that the data has not been transmitted in error. If an error is found, the sender will be requested to retransmit the data, thus ensuring that the signal data received by the control system is accurate.

Performance Features

High-precision Signal Processing: During the signal conditioning and conversion process, the turbine's operating parameters can be accurately acquired and transmitted due to its high-precision A/D conversion (with an accuracy of ±0.1% - ±0.5% of full-scale accuracy) and precise digital signal processing. This is essential for accurately monitoring the condition of the turbine, for example, in shaft vibration monitoring, where small changes in vibration can be accurately measured and potential faults detected in a timely manner.

Multi-Channel Signal Processing Capability: With multiple input channels, many different types of turbine sensors can be connected simultaneously. The number of channels may vary from 8 - 16 depending on the model. This multi-channel design allows for comprehensive monitoring of multiple turbine parameters, such as simultaneous monitoring of shaft vibration, shaft displacement, and multiple RPM signals at different locations, providing richer data for turbine condition assessment.

Compatibility and Communication Flexibility: Supporting a variety of industrial communication protocols makes it easy to integrate with control systems and monitoring equipment from different manufacturers. This compatibility and communication flexibility helps to build a comprehensive turbine monitoring network in complex industrial automation systems, enabling data sharing and collaborative processing.

Strong anti-interference capability: Designed with the characteristics of industrial environments in mind, it is able to effectively resist electromagnetic interference and noise interference in industrial environments through operations such as filtering in signal conditioning and error-correction mechanisms in communication protocols. This ensures that the operating parameters of the turbine can still be accurately collected and transmitted in harsh industrial sites, such as the turbine room of a power plant.

Technical Parameters

Input parameters:

Number and range of analogue input channels: typically 8 - 16 analogue input channels, capable of receiving a wide range of analogue signal types. For example, the voltage signal range may be - 10V - + 10V, 0 - 10V, etc., and the current signal range may be 4 - 20mA, 0 - 20mA, etc., in order to adapt to the output signals of different turbine sensors.

Digital Input Types and Level Standards: Supports a variety of digital signal types such as TTL (Transistor-Transistor Logic) levels, CMOS (Complementary Metal-Oxide-Semiconductor) levels, TTL levels typically range from 2V - 5V for high levels and 0V - 0.8V for low levels, and CMOS level ranges vary depending on the specific device.

Input Signal Resolution (Analogue Inputs): Analogue input channels can have a resolution of 12 - 16 bits, with higher resolutions enabling more accurate acquisition of analogue signals.

Conversion parameters (A/D conversion):

A/D Conversion Accuracy: The conversion accuracy is ±0.1% - ±0.5% full-scale accuracy, ensuring highly accurate signal conversion.

Sampling Frequency Range: The sampling frequency range is wide, generally ranging from a few thousand times per second to several hundred thousand times per second, which can be set according to the actual application requirements. For example, for high-frequency vibration monitoring, a higher sampling frequency may be used; while for low-frequency shaft displacement monitoring, a lower sampling frequency may be used.

Communication parameters:

Supported communication protocols: It supports a variety of industrial communication protocols such as Profibus - DP, Modbus, etc., which is convenient for communication with the control system and other devices.

Communication rate: The communication rate varies according to the adopted communication protocol and connection mode. For example, in Profibus - DP communication, the communication rate can reach 12Mbps; in using Modbus protocol to communicate through serial port, the communication rate can be between 9600bps - 115200bps.

Physical parameters:

Dimensions: The external dimensions are designed according to the installation requirements and may range from 10cm - 20cm in length, 5cm - 10cm in width, and 3cm - 8cm in thickness, making it easy to be installed in a control cabinet or a specific location on the equipment.

Weight: Light weight, usually between 100g - 500g, will not cause excessive burden on the installation and structure of the equipment.

Environmental parameters:

Operating Temperature Range: Capable of operating in a temperature range of - 20°C - + 60°C, adapting to different industrial site temperature conditions.

Humidity range: Relative humidity range is usually 10% - 90% (non-condensing), ensuring normal operation in different humidity environments.