Petrochemical drives offer PTC monitoring for Ex motors

Published: 13 June, 2013

At the recent Hannover Fair, Siemens announced a range of frequency converters targeting the chemical, oil and gas, and process industries. The Sinamics G180 converters, available with output ratings from 2.2–6,600kW and for voltages from 230–690V, incorporate industry-specific functions such as dV/dT and line filters, and Atex-certified PTC monitoring for Ex motors.

The converters have evolved from the earlier Dynavert T family. They are aimed at applications such as pumps, fans, compressors, conveyors, mixers and extruders.

Combining the Atex-certified temperature monitoring with a built-in Safe Torque Off function allows the converters to control explosion-proof motors without needing a line contactor. Evaluation is performed using a PTC thermistor embedded in the motor windings.

Siemens' G180 converters target the process and petrochemical sectors

The built-in dV/dT filter supports cable runs of up to 350m long between the converter and the motor. The drives can be dimensioned using Siemens’ Sizer and DT Configurator engineering tools.