Siemens 6SE6440-2UD33-0EA1 MICROMASTER 440 Frequency Inverter Product Description

Overview

Siemens 6SE6440-2UD33-0EA1 is a MICROMASTER 440 (MM440) general-purpose variable frequency drive. This 6SE6440-2UD33-0EA1 is 30 kW constant torque rating, 3×380–480 V AC, without built-in EMC filter, E frame size, no keypad included. It is an end-of-life legacy product (discontinued since Oct 1, 2019), widely used for pump, fan, conveyor and general asynchronous motor speed control, for on-site equipment maintenance and spare‑part replacement of MM440 drive systemsIndustry M....

Features

Siemens 6SE6440-2UD33-0EA1 supports V/F control and sensorless vector control, offering stable low-speed torque for variable torque and constant torque loads. This MM440 inverter integrates RS485 USS communication port by default; optional PROFIBUS module can be added for PLC interconnection. 6SE6440-2UD33-0EA1 has built-in braking chopper, supports external brake resistor for rapid stop. It has comprehensive protection functions: electronic overload, phase loss, phase imbalance, overvoltage, undervoltage, short circuit and motor PTC thermal protection. Parameter setting can be done via BOP/AOP operator panel or Siemens STARTER software. It supports multiple acceleration/deceleration curves, slip compensation and automatic stall prevention. IP20 protection is suitable for cabinet installation.

Specs

• Brand: Siemens

• Series: MICROMASTER 440

• Model: 6SE6440-2UD33-0EA1

• Rated power (CT constant torque): 30 kW

• Rated power (VT variable torque): 37 kW

• Input: 3×380–480 V AC ±10%, 47–63 Hz

• Overload capacity: 150% for 60 s, 200% for 3 s

• EMC filter: Not integrated

• Built-in: Brake chopper, USS RS485

• Protection class: IP20

• Dimensions (H×W×D): 650 × 275 × 245 mm

• Operating temperature: -10 ~ +50 °C

• Standard: CE, UL

• Lifecycle: Discontinued

Principle

Siemens 6SE6440-2UD33-0EA1 converts three-phase AC power into DC bus through rectifier, then modulates IGBT conduction angle to generate adjustable frequency and voltage three-phase AC output for the motor. Vector control improves torque stability at low speed. When decelerating, regenerative energy is consumed by external braking resistor through the internal chopper. The sampling circuit continuously monitors current and voltage, and triggers fault shutdown once exceeding protection thresholds. It stores fault codes and runtime data for troubleshooting.

Applications

Siemens 6SE6440-2UD33-0EA1 is deployed in water supply pumps, cooling fans, HVAC systems, material conveyors and general industrial processing equipment. This MM440 inverter reduces starting impact and realizes energy-saving speed regulation. 6SE6440-2UD33-0EA1 fits legacy drive overhaul and spare replacement of MICROMASTER 440 series 30 kW inverters.

Installation & Maintenance Notes

Follow official Siemens MM440 operating manual during installation of 6SE6440-2UD33-0EA1. Use shielded motor cable and separate routing from signal cables; add external EMC filter if site EMC requirements apply. Fully discharge DC bus after power-off before opening the unit. Back up all motor parameters, communication settings and ramp curves before replacement. After replacement, verify motor nameplate data, USS address and brake resistor configuration. Confirm exact part number 6SE6440-2UD33-0EA1; filtered versions and different power variants cannot be substituted directly.