1. Model Code Breakdown

• 31C: MOVITRAC 31C compact series

• 008: 0.75 kW rated output power

• 503: 380–500 VAC (400 V class)

• 4: Three‑phase AC input / 4‑quadrant (brake chopper built‑in)

• 00: Standard version (RS‑485, no PROFIBUS)

2. Electrical Ratings (400 V / 50–60 Hz)

• Rated Output Power: 0.75 kW

• Input: 3×380–500 VAC, 50/60 Hz

• Rated Input Current: 2.1 A (400 V)

• Rated Output Current: 2.5 A (continuous)

• Output Capacity: 1.8 kVA

• Output Voltage: 0–480 VAC, three‑phase

• Output Frequency: 0–400 Hz

• Control Modes: V/f open‑loop / sensorless vector

• Overload: 150% for 60 s

• Switching Frequency: 4/8/12/16 kHz (selectable)

• STO (Safe Torque Off): Standard (PL d / SIL2)

3. Mechanical & Environmental

• Protection Class: IP20

• Cooling: Natural convection (no fan)

• Operating Temp: 0 °C … +45 °C (full load)

• Storage Temp: −25 °C … +70 °C

• Humidity: 5–95%, non‑condensing

• Altitude: ≤1000 m (no derating)

• Dimensions (W×H×D): ~184 × 281 × 170 mm

• Weight: ~1.8–3.0 kg

4. Interfaces & Terminals

Control I/O

• Analog Input: 0–10 V / 0–20 mA (speed reference)

• Digital Inputs: 6 × 24 VDC (programmable)

• Relay Outputs: 2 × programmable (250 VAC / 30 VDC, 3 A)

• Motor Thermistor: PTC/KTY input

Communication

• Onboard RS‑485 (Modbus RTU) – standard for ‑00 version

• No integrated PROFIBUS (use ‑20 for PROFIBUS‑DP)

• Optional: FBG 31C keypad (parameter setup/display)

Power Terminals

• X1: L1/L2/L3 (three‑phase input)

• X2: U/V/W (motor output) + PE

• DBU: Brake resistor connection (internal chopper)

5. Core Functions

• V/f open‑loop / sensorless vector control (low‑speed high torque)

• Adjustable accel/decel: 0.1–600 s

• Integrated DC braking & dynamic braking

• Energy‑saving mode

• Local/terminal/communication control

• Slip compensation (speed stability)

• Soft start/stop (reduce mechanical stress)

• Built‑in PID (constant pressure/speed)

• Parameter save/restore/copy

6. Protection Features

• Overcurrent / thermal overload

• Overvoltage / undervoltage

• Input phase loss

• Inverter overtemperature

• Electronic motor thermal protection

• Output short circuit / earth fault

• Anti‑stall

• ESD protection (control terminals)

• Hardware STO (PL d / SIL2)

7. Applications

• Small three‑phase motor speed control

• Light industrial automation

• Fans, pumps (energy saving)

• Packaging/logistics equipment

• Conveyors, textile machinery

• RS‑485/Modbus RTU systems (standard communication)

8. Compliance

• CE (Low Voltage, EMC)

• EN 61800‑3 (EMC)

• RoHS

• STO: PL d, SIL2

Key Difference vs 31C007‑503‑4‑00

• 31C008‑503‑4‑00: Size 1, 2.5 A output current, larger dimensions

• 31C007‑503‑4‑00: Size 0, 2.4 A output current, compact dimensions

  Both are 0.75 kW, standard RS‑485 versions.