This technical manual guide covers the installation, hardware configuration, network integration, and troubleshooting procedures needed to keep your heavy-duty HVAC systems running efficiently. Hardware Architectural Profile
| Problem | Likely Cause | Manual Reference | Solution | |---------|--------------|------------------|----------| | No display | Power supply failure | Section 2.1 | Check voltage at terminals. Replace fuse if present. | | Wrong temperature reading | Incorrect sensor type selected | Section 4.3 (Input config) | Change Sn parameter to match actual sensor (e.g., K for Type K). | | Output relay never turns off | Setpoint too high or sensor error | Error code table | Check for E-01 (sensor open). Clean or replace sensor. | | Display shows HHHH | Temperature over-range | Section 5.2 | Reduce heat source. Check sensor placement. | | Settings reset after power cycle | Failed EEPROM or battery | Section 6 (Maintenance) | Perform factory reset. If repeats, replace unit. | mt3021 manual
| Parameter | Value / Range | Units | Remarks | |-----------|---------------|-------|---------| | | 3 × 200‑480 V AC | V | 50/60 Hz, selectable via DIP switch | | Output Power | 0.5 – 22 kW | kW | Continuous rating, 10 % overload for 60 s | | Output Voltage | 0 – 480 V AC | V | Vector‑controlled output | | Output Current | 0 – 50 A per phase | A | Current limit configurable | | Efficiency | ≤ 96 % (typ) | % | At 75 % load | | Control Interface | IEC‑61131‑3 compatible PLC, Modbus‑RTU (RS‑485), CANopen, Ethernet‑IP | – | Dual‑port communication | | User Interface | 3‑button keypad + 2‑line LCD (128 × 64 px) | – | Optional HMI add‑on | | Protection Functions | Over‑voltage, under‑voltage, over‑current, ground fault, over‑temperature, motor stall | – | Configurable trip levels | | Environmental | Operating: –20 °C to +60 °C; Storage: –40 °C to +85 °C | °C | Conformal coating on PCB | | Dimensions (L × W × H) | 210 × 140 × 150 mm | mm | DIN‑rail mounting | | Weight | 3.5 kg | kg | – | | | Wrong temperature reading | Incorrect sensor