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Two Solutions for High-speed Spindles in the Low-voltage Range

Press releases
SD4S and SD4B for high-speed spindles in the low-voltage range

Frequency Converters SD4S and SD4B by SIEB & MEYER

With SD4S and SD4B, the Lueneburg based company SIEB & MEYER AG offers two frequency converters specially designed for high-speed spindles in the low-voltage range. Both variants can operate asynchronous, synchronous and IPM motors up to speeds of 240,000 rpm (4,000 Hz) without sensors.


Low-voltage high-speed spindles are used, for example, in dental CAD/CAM machines, machine tools for the watchmaking industry or as dressing spindles in grinding machines. The defining feature of these spindles is an operating voltage in the range of 24 .. 48 VAC. Frequency converters with a supply voltage at mains level (230/400 VAC) – which is the standard – are not suitable for low-voltage spindles due to the high DC link voltage.

SIEB & MEYER has therefore developed two solutions within the device family SD4x. Both devices are specially suited to operating high-speed spindles in the low-voltage range. The low-voltage versions of the SD4S series are optimized for single-phase voltage supply of 45 .. 60 VAC. Users benefit from the fact that this voltage supply is easily realized by means of a suitable isolating transformer.


SD4B with only 25 mm structural width

Whenever machines provide a powerful DC supply with the required voltage level already or when the frequency converter must come with a compact construction volume and small width, SD4B is the variant of choice. SD4B is suitable for supply voltages of 24 .. 80 VDC and sets standards in the market with its structural width of only 25 mm.

For communication purposes, SD4S as well as SD4B offer interfaces for CANopen, Modbus RTU/TCP and RS232/485 beside the standard Ethernet interface for the parameterization. Optionally, interfaces for EtherCAT or POWERLINK are available.