Overview

The YOKOGAWA UM331-00 Digital Indicator is a versatile device tailored for process control applications. It offers accurate measurement and indication of various input signals, including thermocouples, RTDs, and standard voltage signals.

Technical Specifications

PV Input Signals

• Number of Inputs: 1 (terminals 11 - 12 - 13)
• Input Type: Universal input system (selectable via software)
• Sampling Period: 250 ms
• Burnout Detection: Functional for TC, RTD, and standard signals (0.4 to 2 V or 1 to 5 V)
  • Options: Upscale, downscale, and off can be specified
• Measurement Current (RTD): Approximately 0.13 mA
• Allowable Wiring Resistance: Maximum 150 Ω/wire for RTD input; conductor resistance between three wires should be equal
• Noise Rejection Ratio:
  • 40 dB (50/60 Hz) or more in normal mode
  • 120 dB (50/60 Hz) or more in common mode
• Applicable Standards: JIS, IEC, DIN (ITS-90) for thermocouples and RTD

Loop Power Supply

• Power Supply:
  • 14.5 to 18.0 V DC, max. 21 mA (with protection circuit against field short-circuit)
  • 21.6 to 28.0 V DC, max. 30 mA (for models with 24 V DC loop power supply)

Retransmission Output

• Number of Outputs: 1 (terminals 16 - 17)
• Output Signal: 4-20 mA DC