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Product Information

  • Current Consumption: -
  • Frequency: 134.2kHz
  • Memory Size: 32KB
  • Module Interface: Serial
  • SVHC: No SVHC (15-Jun-2015)
  • Supply Voltage Max: 24V
  • Supply Voltage Min: 10V


RI-STU-251B-30 is a low-frequency (LF) reader provides all the functionality required to communicate with TI 134.2kHz LF transponders. RI-STU-251B Reader/Writer is capable driving a variety of antennas with inductance ranges from 26.0µH to 27.9µH including TI standard antennas such as gate antennas, stick antennas. The RI-STU-251B includes an automatic antenna resonance tuning feature which further reduces the need for maintenance and simplifies installation. It also supports both RS232 and RS422/485 interface standards. The Series 2000 Reader S251B provides all RF and Control Functions to communicate with 134.2kHz HDX/FSK transponders. It sends an energizing signal to the transponder, modulates the RF signal to send data to the transponder, decodes and checks the received transponder data and transmits it via a standard serial interface. The reader includes Dynamic Auto Tuning (DAT) function that automatically tunes a standard antenna to resonance and keeps it tuned during operation.


  • Best in class performance through patented HDX (Half Duplex) technology
  • Automatic antenna tuning
  • High power output
  • Proven in harsh industrial environments
  • Easy to install and use
  • Inductance ranges from 26.0μH to 27.9μH
  • Operating temperature is –20 to +70°C
  • 64kByte EPROM for firmware, 1kBit EEPROM for Configuration, 32 kByte RAM for data
  • ASCII with Xon/Xoff handshake, TIRIS bus protocol
  • 8 configurable digital I/Os, 2 open collector outputs


  • System Monitoring
  • Security
  • RF Communications
  • Wireless

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Availability:  3

  • 3 in stock for same day shipping
Check stock and lead times
    More stock available week commencing 9/28/15

Price for: Each 1

Minimum order quantity: 1

Order multiple quantity: 1

Price: $800.00 $800



Quantity List Price
1+ $800.00

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