IS200VRTDHID - RTD Processor Board

SPECIFICATIONS

Part No.: IS200VRTDHID
Manufacturer: General Electric
Country of Manufacture: United States of America (USA)
Temperature: 0 to 60 °C
Number of channels: 16
Technology: Surface-mount
Product Type: RTD Processor Board
Availability: In Stock
Series: Mark VI

Functional Description

IS200VRTDHID is an RTD Processor Board developed by GE. It is a part of the Mark VI control system. The Resistance Temperature Device (RTD) Input (VRTD) board is designed to accurately measure temperature using RTD sensors. Here's how it operates: The board accepts 16 three-wire RTD inputs, providing ample capacity for temperature monitoring in industrial applications. These inputs are connected to an RTD terminal board (such as TRTD or DRTD) via cables with molded fittings.

Signal Transmission

• The terminal board is connected to the VME rack where the VRTD processor board is located.
• The board excites the RTDs (Resistance Temperature Devices), initiating the temperature measurement process.
• The resulting signals from the RTDs are then transmitted back to the VRTD board for processing.

Digital Conversion

• Upon receiving the signals from the RTDs, the board converts them into digital temperature values.
• These digital temperature values are then transferred over the VME backplane to the VCMI (VME Control and Monitoring Interface) board, which further communicates with the controller.

Integration with the Controller

• The controller receives the digital temperature values from the VCMI board, allowing it to monitor and control temperature-dependent processes within the industrial system.
• This seamless integration ensures accurate temperature measurement and control, contributing to the overall efficiency and reliability of the system.

Excitation Current

• The board supplies a 10 mA DC multiplexed excitation current to each RTD through the terminal board.
• This excitation current is not continuous but is provided intermittently to energize the RTDs for temperature measurement.

Signal Processing

• The resulting signal from each RTD returns to the VRTD board for further processing.
• It utilizes a Voltage Controlled Oscillator (VCO) type Analog-to-Digital (A/D) converter.
• This converter employs voltage-to-frequency converters and sampling counters to convert the analog signals from the RTDs into digital values.

Scanning Frequency

• The converter samples each signal and the excitation current four times per second in normal mode scanning.
• In fast mode scanning, the sampling frequency is increased to 25 times per second.
• The sampling interval is adjusted based on the power system frequency to ensure accurate temperature measurements.

Linearization and RTD Types

• Software implemented in the digital signal processor performs linearization of the RTD signals.
• This allows for the accurate conversion of temperature values, with support for 15 different RTD types.

Fault Detection and Channel Management

• The board detects open and short circuits in the RTD inputs by monitoring for out-of-range values.
• If an RTD is determined to be outside the hardware limits, it is automatically removed from the scanned inputs to prevent adverse effects on other channels.
• Repaired channels are reinstated automatically after 20 seconds or can be manually reinstated by the user.

The WOC team is always available to help you with your Mark VI requirements. For more information, please contact WOC.

Frequently Asked Questions

What is IS200VRTDHID?
It is an RTD Processor Board developed by GE under the Mark VI series.

How does the VRTD board supply excitation current to RTDs?
The board provides a 10 mA DC multiplexed excitation current to each RTD through the terminal board.

What type of A/D converter does the board use?
The board utilizes a Voltage Controlled Oscillator (VCO) type Analog-to-Digital (A/D) converter.

How often are RTD signals sampled by the RTD board?
In normal mode scanning, signals are sampled four times per second, while in fast mode scanning, the sampling frequency is increased to 25 times per second.

What types of RTD linearization does the VRTD board support?
The board supports linearization for 15 different RTD types, ensuring accurate temperature measurement across various applications.

How does the VRTD board detect faults in inputs?
Faults such as open and short circuits in inputs are detected by monitoring for out-of-range values.

What happens if an RTD is determined to be outside hardware limits?
If found to be outside hardware limits, it is automatically removed from the scanned inputs to prevent adverse effects on other channels.