Overview

The RTD input module is an intelligent block transfer module that interfaces analog input signals with any Allen-Bradley programmable controllers that have block transfer capability. Block transfer programming allows for the movement of input data words from the module’s memory to a designated area in the processor data table during a single scan, as well as configuration words from the processor data table to the module memory.

Specifications

• Module Capacity:

  • Six RTD input channels

• Module Location:

  • 1771 I/O Chassis

• Sensor Type:

  • 100 ohm platinum (alpha = 0.00385)
  • 10 ohm copper (alpha = 0.00386)
  • Other types may be used with reporting in ohms only

• Units of Measure:

  • Temperature in °C
  • Temperature in °F
  • RTD resistance in ohms (10 milliohms or 30 milliohms resolution)

• Temperature Range:

  • Platinum: -200 to +870 °C (-328 to 1598 °F)
  • Copper: -200 to +260 °C (-328 to +500 °F)

• Resistance Range:

  • 1.00 to 600.00 ohms

• Resolution:

  • Platinum: 0.1 °C (0.1 °F)
  • Copper: 0.3 °C (0.5 °F)

• Sensor Excitation:

  • 1 mA constant current source supplied by module

• Input Isolation:

  • Dielectric Test: 1000V peak channel to channel, channel to backplane, for 1 second
  • Common Mode Rejection: 120 dB @ 60 Hz up to 1000V peak
  • Common Mode Impedance: Greater than 10 megohms
  • Normal Mode Rejection: 60 dB @ 60 Hz

• Input Overvoltage Protection:

  • 120V rms continuous

• Open RTD Response Time:

  • Open excitation (terminal A) to overrange: <0.5 sec
  • Open common (terminal C) to underrange: <0.5 sec
  • Open sense (terminal B): drift high

• Scan Time (all 6 channels):

  • 50 ms

Environmental Conditions

• Operating Temperature:

  • 0 to 60 °C (32 to 140 °F)
  • Ambient changes greater than 1.0 °C/minute may temporarily degrade performance during periods of change.

• Storage Temperature:

  • -40 to 85 °C (-40 to 185 °F)

• Relative Humidity:

  • 5 to 95% non-condensing

Backplane Power Consumption

• Power Consumption:
  • 4.25W maximum, 0.85A at 5V

Keying

• Between 10 and 12
• Between 28 and 30

Field Wiring Arm

• Catalog Number: 1771-WF