General Information The UT2800-1/HB is a 1/4 DIN high-precision digital controller with a fixed high-limit alarm (HB). It supports universal sensor inputs and is designed for industrial temperature and process control applications. 2. Features Model: UT2800-1/HB Built-in HB High Alarm: Dedicated high-limit alarm relay output Universal Input: Thermocouple (K, J, E, T, N, R, S, B); RTD (Pt100); DC 4–20 mA, 0–10 V Dual LED Display: PV (process value) / SP (setpoint) Control Modes: ON/OFF, PID with auto-tuning Alarm Output: 1 relay (250 VAC, 3 A resistive) for HB high alarm Power Supply: 100–240 VAC, 50/60 Hz Dimensions: 96 × 96 × 100 mm (1/4 DIN) Accuracy: ±0.1% of full scale 3. Safety Precautions Disconnect power before wiring or maintenance. Separate signal and power cables to avoid electrical interference. Avoid installation in locations with vibration, corrosive gas, direct sunlight, or condensation. Only qualified personnel may perform wiring and parameter setup. Do not disassemble the unit; no user-serviceable parts inside. 4. Installation 4.1 Panel Mounting Cut a 92 × 92 mm square hole in the panel (thickness 1–5 mm). Insert the controller from the front. Secure with rear mounting brackets and tighten screws. Ensure the front panel is flush. 4.2 Terminal Wiring 1–2: Power (100–240 VAC) 3–4: HB Alarm relay (NO/COM) 5: Not used (reserved) 6–7: Sensor input (+/–) 8: Common ground (GND) 5. Front Panel Operation 5.1 Panel Keys & Indicators PV Display (Upper): Process value (temperature/process variable) SP Display (Lower): Setpoint or parameter value HB Indicator: Lights when high alarm is active SET Key: Enter/confirm parameters ▲/▼ Keys: Adjust values, select parameters ◄ Key: Move cursor left 5.2 Basic Operation Power-On The unit performs a self-test, then displays PV and SP normally. Setpoint Adjustment Press SET briefly (SP display flashes). Use ▲/▼ to modify the setpoint. Press SET or ENT to save. Parameter Entry Hold SET for 3 seconds to enter setup mode. Use ▲/▼ to select a parameter. Press SET to edit. Adjust value with ▲/▼ and ◄. Press SET to save. Hold SET 3 seconds to exit. 6. HB High Alarm Parameters HB.L: High alarm limit (PV ≥ HB.L → alarm ON) HB.HY: Alarm hysteresis (prevents rapid on/off cycling) HB.MD: Alarm mode (normally open / normally closed) When PV exceeds HB.L, the relay activates and the HB lamp lights. 7. Input Type Selection In setup mode, set IN.TYP to: K/J/E/T/N/R/S/B: Thermocouple Pt100: RTD 4–20mA / 0–10V: Analog input 8. Error Codes Err 01: Sensor open circuit Err 02: Input overrange Err 03: Input underrange Err 04: Internal hardware fault Err 05: HB alarm circuit error 9. Specifications Input: Universal (TC/RTD/DC) Control: ON/OFF, PID auto-tuning Alarm: 1×HB high-limit relay Accuracy: ±0.1% FS Power: 100–240 VAC, 50/60 Hz Display: Dual 4-digit LED Operating Temp: 0–50°C Humidity: 10–90% RH (non-condensing) Weight: Approx. 0.5 kg 10. Maintenance Clean the front panel with a soft, dry cloth. Do not use solvents or water. Check terminal connections periodically for tightness. Calibrate annually for precision applications.