Success Story 1 Drive Technology

Transcript

Drive Technology Success Story 1 Faster in Form SINAMICS G110 in a lathe Advance 3 / 2005 In conventional lathes the speed is adjusted by a graduated belt drive by which it is adapted to different kinds of wood and diameters. In the DMV-200 made by the Scheppach company for example with five stepped spindle speeds. For more flexible adaptation of the spindle speed to the processing steps a variable-speed drive SINAMICS G110 now gives new impetus to the machine. The conversion was simple because the connection of the drive motor for the drive belt pulley - of a three-phase current motor with 400 V/ 50 Hz feed and an output of 0.75 kW - could be changed from star circuit to delta circuit on the terminal side thus giving a motor supply voltage of 230 V/50 Hz. The converter generates variable speeds in three-phase asynchronous motors and is itself connected to a single-phase 230 V mains. Simple modernization - trouble-free installation In order to enable easy redundancy later the standard switch-plug combination for the connection voltage 400 V/50 Hz to the motor junction box was retained. A second cable screw gland was mounted on the junction box housing for the converter connection and a completely new wiring up to the converter outlet installed. Thanks to its compact size the converter could be installed directly next to the machine within the operators reach. The cable connection proved to be an advantage because the arrangement of the power connections on the converter, namely the mains connection on top and motor outlet on the bottom, is based on a contactor and therefore familiar to all electricians. The built-in class B EMC filter enables trouble-free operation on the 30 mA fault current circuit breaker. Direct access to all parameters of the converter The commissioning is no problem for electricians either because the optional, pluggable Basic Operator Panel (BOP) enables access to all parameters of the converter and important diagnostic functions. In fast commissioning mode only the most important parameters are addressed such as motor data, run-up and run-down times as well as the electronic motor potentiometer function activated. With the up/down keys of the plugged BOP the speed setpoint can easily be adjusted in steps of 0.1 Hz. An externally installed potentiometer for setting the nominal value is unnecessary so that no further wiring is required. If the operator wants to prevent unauthorized use of the lathe, he can quite simply remove the BOP .The easy assembly, the simple cooling by the ribbed heat sinks and the easily operable frequency control without speed feedback speak in favor of the SINAMICS G110 as the example of the lathe demonstrates. Whereas the necessary speed adjustment could only previously be performed at standstill with the motor switched off due to the different workpiece sizes or changing machining processes, it is now possible to set the belt drive to a fixed transmission (1,000 rpm) and to dispense with the complicated manual speed adjustment. The maximum motor speed is stored in the converter software. The spindle speed can be varied from zero to about 3,000 rpm. The clearance-free, smooth running guarantees precision machining of the workpieces. The mission of the loosing and tightening of the belt tensioning device and the implementation of the belt itself results in a time advantage of up to 30% - depending on the complexity of the workpiece to be machined. www.usa.siemens.com/drives