6SE6430-2UD31-8DA0 Variable Frequency Drive MicroMaster 430 18.5kW 3-ф/380

6SE6430-2UD31-8DA0 — a MICROMASTER 430 rated 18.5 kW, 3-phase 380 V supply, rated current 38 A. Built for variable torque — pumps and fans, V/f control with about 110% overload. Not for heavy starting or constant-torque loads.

Typical applications:

• Second-lift water-utility pump or booster station
• Large HVAC fan or cooling-tower fan in a mall/office
• Cascade of 2–3 pumps under one PID loop

Note: the 6SE6430-2UD… variant has no built-in EMC filter; pick it when a filter is already in the cabinet or is not required on site. The series is discontinued — for a like-for-like replacement by power and current we suggest the SINAMICS G120P successor or the in-stock Veichi AC310.

Siemens MICROMASTER 430 — a VFD for pumps and fans (variable torque)

The MICROMASTER 430 (MM430) is Siemens' dedicated series for variable-torque loads — centrifugal pumps and fans. It is not a general-purpose drive: overload is around 110%, and control is V/f only (no closed-loop vector with an encoder). In the package we service the series spans 7.5 to 90 kW, all models 3-phase 380 V. To be upfront: the line is discontinued, so for new projects people usually look at the successor or at available alternatives.

What the MM430 is for

• Water supply and boosting: centrifugal pumps, pump stations. The built-in PID holds pressure without a separate controller.
• Pump cascade: the drive can stage up to three additional motors via relay outputs — ready-made logic for booster sets.
• Ventilation and HVAC: supply/exhaust fans, AHUs, cooling-tower fans. The parabolic V/f curve plus ECO mode give real savings versus a damper.

How the MM430 differs from general-purpose drives

In short: the MM430 does its job well on pumps and fans, but it is deliberately tailored to that class. If you need torque headroom, that is a different series.

When the MM430 is NOT a fit

• Conveyors, hoists, crushers, extruders — anything with high breakaway torque. You need a vector drive here; see our Veichi AC310 series.
• You need Modbus RTU out of the box for modern SCADA — the MM430 uses USS/PROFIBUS. Consider modern frequency inverters with Modbus.
• A new project with warranty and support — choose the SINAMICS G120P successor or an available alternative.

How to replace a MICROMASTER 430

Siemens' direct pump/fan successor is the SINAMICS G120P. If you need a drive that is in stock and easy to service in Ukraine, we usually suggest the Veichi AC310 (PID, Modbus RTU, sensorless vector) or the simpler Veichi AC10 for basic pump/fan duty.

Our experience with the MM430

We regularly get enquiries about MM430 units that have run for years on water utilities and ventilation — the series earned its reputation as a reliable workhorse. Two questions come up most: picking a replacement, and the difference between the 6SE6430-2AD… (with EMC filter) and 6SE6430-2UD… (without filter) variants. If you have an MM430 and need a like-for-like replacement by power and current, we can help.