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CM3 RTD Module Features

CM3 RTD Module​


The CM3-SP04ERO RTD Module from CIMON is designed for precise temperature measurement in industrial automation systems. This module supports PT100, JPT100, PT1000, and Ni1000 RTD sensors, converting resistance values into accurate digital temperature readings. With high-resolution 14-bit or 16-bit digital output, rapid conversion speeds, and built-in wire break detection, the CM3-SP04ERO ensures reliable and stable operation in HVAC, process control, and industrial monitoring applications. Its photocoupler isolation and multi-channel support make it a versatile and robust solution for temperature sensing needs.

Features​

The CM3-SP04ERO measures the input from a resistor and converts it into a 14-bit digital temperature (°C/°F) value.

  • The CM3-SP04ERO converts temperature from the following resistor types into a 1-digit number after the decimal point. It outputs a digital value in the range 0 ~ 16,000.
    • Platinum100 (PT100)
    • Platinum1000 (PT1000)
    • Japanese Platinum100 (JPT100)
    • Nickel1000 (Ni1000)
  • The CM3-SP04ERO converts the following temperatures based on their resistor types into a digital value between 0 ~ 16,000 (-8,000 ~ 8,000).
    • Platinum100 (PT100), Platinum1000 (PT1000), and Japanese Platinum100 (JPT100)
      • -200°C ~ 600°C (-328°F ~ 1,112°F)
    • Nickel1000 (Ni1000)
    • -50°C ~ 160°C (-58°F ~ 320°F)
  • The CM3-SP04ERO can show a temperature range based on the following resistor types. If the value is digital, the shown range is -192 ~ 16,191 (-8,192 ~ 8,192).
    • Platinum100 (PT100), Platinum1000 (PT1000), and Japanese Platinum100 (JPT100)
      • -250°C ~ 650°C (-418°F ~ 1,202°F)
    • Nickel1000 (Ni1000)
      • -60°C ~ 170°C (-76°F ~ 338°F)
  • If the minimum and maximum temperature values are set up, the temperature is converted into the minimum value, 0 (-8,000), and the maximum value, 16,000 (8,000).
  • Broken cables, thermocouple, or out-of-range measurements by the channels can be detected.
  • There are 4 channels on the CM3-SP04ERO expansion module.
  • The CM3-SP04ERO has an LED indicator for status.
    • Normal: LED is ON.
    • Error: LED is blinking.

Output:

  • PT100 & JPT100: 0°C/32°F → 100.0Ω output
  • PT1000: 0°C/32°F → 1,000.0Ω output
  • Ni1000: 0°C/32°F → 1,000.0Ω output

Example​


  1. The resistance of the PT100 sensor varies depending on changes in the surrounding temperature.
  2. The CM3-SP04ERO performs linearization for the resistance input of RTD which is non-linear (shown above).
  3. The temperature is stored in the internal memory of the CM3-SP04ERO as a converted temperature.
  4. The CM3-SP04ERO uses the converted temperature or digitally-converted value stroed in buffer memory in the module using the FROM instruction in the scan program.