SD2S Frequency Converter

The Specialist for High-Speed Applications

The Expert for High-speed Applications


Powerful, flexible and compact – these words describe the drive amplifier SD2S by SIEB & MEYER. Using the available operation modes synchronous and asynchronous motors with speeds up to 480,000 rpm can be driven by SD2S, especially in respect to low motor heating in high-turning motors with small rotors. Small motor temperatures are the basis for a high machining quality. Depending on the application, the operation can be carried out with or without encoder. For the operation with an encoder, SD2S offers the possibility to evaluate the common encoder systems existing on the market. SD2S is connected to the higher-ranking control via analog reference values (+/-10 V), digital I/Os, RS232, USB, CAN bus,  EtherCAT or Profibus (via SERVOLINK respectively Anybus adapter).

Robust and Simplified

SD2S offers two drive functions characterized by easy parameterization and a robust operation for applications up to 120,000 rpm. For asynchronous motors, the drive function V/f-PWM is used. Using the V/f characteristic curve, the user can carry out the graphically aided parameterization of the motor. The V/f characteristic curve is an established form of motor parameterization, the user can take advantage of the experience gained in this field.


The SVC (Sensorless Vector Control) drive function is provided for synchronous motors and is based on the equivalent circuit diagram usually found on the motor data sheet. SVC allows 4-quadrant operation of high speed synchronous motors and generators. The SD2S can be used for high speed applications such as turbo blowers or turbines for utilization of process energy.

Technology Functions for Grinding Applications

Multi parameter sets – The flexibility of grinding machines largely depends on the possibility of a fast and simple use of grinding spindles. The feature of saving up to 64 motor parameter sets in the drives enables the variable operation with different motors. The number of parameter sets can be encoded via the digital inputs or alternatively via the provided data interfaces.

Gap elimination – The integrated technology functions for the gap elimination allow an efficient machine operation. This is especially advantageous, if an external acoustic emission evaluation is not possible for technical or financial reasons.


New: High Protection Rating

SIEB & MEYER has extended the proven SD2S series of frequency converters by a new stand-alone version with a high protection rating. Therefore, the frequency converter can be used outside a switch cabinet making the extension and modification of machinery and equipment more easy. In addition, concepts with decentrally arranged frequency converters are feasible.

Usually, the space in switch cabinets is tight and existing capacities are fully utilized. The new, self-sufficient SD2S design offers customers the opportunity to put additional frequency converters into operation without any financial and organizational effort.

Key figures:

  • air-cooled stand-alone model

  • mains voltage of 5 kVA @ 3 x 400VAC

  • compact dimensions: 107 mm, 413 mm and 315.5 mm (WxHxD)

  • flexible cable passages enable a simple installation or a device replacement

Function - Advantage - Benefit

Extensive drive functions

Function: Freely selectable drive functions, selectable drive functions SVC, V/f-PWM, HS-Block, Servo.
Advantage: The optimal drive function can be selected depending on the application requirements.
Benefit: Best system performance.

Universal motor encoder interface

Function: Resolver, encoder / linear scale (TTL or Sin/Cos), EnDat, Hiperface, SSI, Hall sensor, linear Hall sensor, magnetoresistive sensor, NAMUR sensor.
Advantage: High flexibility in the choice of the motor encoder interface.
Benefit: Low system costs, free choice of the motor manufacturer.

Load Indicator

Function: As standard SD2S offers a highly precise evaluation of the torque-forming current.
Advantage: The evaluation can be used for tool monitoring. These are for example detection of tool breakage, tool wear, gap eliminator (GAP and crash) and an optimal control of the feed rate during the manufacturing process.
Benefit: Low system costs, no need of cost-intensive monitoring sensors.