UT320-30

Overview

UT320-30 is a Yokogawa digital indicating controller with retransmission output and loop power supply (15 V DC standard, 24 V DC optional). It supports universal input signals, advanced burnout detection, and reliable noise rejection for industrial process control.

Identity

• Model: UT320-30

• Type: Digital Indicating Controller

• Standard Type: With 24 V DC loop power supply (Type: 3)

• Optional Functions: None (Code: 0)

PV Input Signals

• Number of Inputs: 1 (terminals 11–12–13)

• Input Type: Universal, selectable via software

• Sampling Period: 250 ms

• Burnout Detection: TC, RTD, standard signals (0.4–2 V or 1–5 V); upscale, downscale, or off selectable

• Bias Current: 0.05 µA (TC/RTD b-terminal)

• Measurement Current (RTD): ~0.13 mA

• Input Resistance: ≥ 1 MΩ (thermocouple/mV), ~1 MΩ (DC voltage)

• Allowable Signal Source Resistance:

  • ≤ 250 Ω (TC/mV input), effect ≤ 0.1 µV/Ω

  • ≤ 2 kΩ (DC voltage input), effect ~0.01 %/100 Ω

• Allowable Wiring Resistance (RTD):

  • Max 150 Ω/wire (equal resistance between three wires)

  • 10 Ω/wire for –150 to 150 °C range (effect: 0.1 °C/10 Ω)

• Allowable Input Voltage: ±10 V DC (TC/mV/RTD), ±20 V DC (DC voltage)

• Noise Rejection Ratio: ≥ 40 dB (normal mode, 50/60 Hz), ≥ 120 dB (common mode, 50/60 Hz)

• Reference Junction Compensation Error: ±1.0 °C (15–35 °C), ±1.5 °C (0–15 °C, 35–50 °C)

• Applicable Standards: JIS, IEC, DIN (ITS-90) for TC and RTD

Loop Power Supply

• Function: Supplies power to two-wire transmitters

• Terminals:

  • 15 V DC: terminals 14–15

  • 24 V DC: terminals 21–22

• Resistor Requirement: 10–250 Ω between controller and transmitter (converts current to voltage for PV input)

• Supply Voltage:

  • 14.5–18.0 V DC, max 21 mA (with short-circuit protection)

  • 21.6–28.0 V DC, max 30 mA (only for 24 V DC loop models)

• Operating Ambient Temperature (24 V DC loop models): 0–40 °C

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