Development of a 63A Test Stand for Grinding Gears and Cutting Units for Simulated Production Lines at Innovent GmbH
Initial situation and project task

Innovent is an engineering and manufacturing company, headquartered in Krefeld, Germany, delivering innovative cutting systems for the textile and paper industries all around the world. The company required a new tester system to be used for development, validation and production of customized cutting machines.

Innovent required a universal measurement and control desk, including various frequency converters for the control of asynchronous and servo drives. All converters were expected to be individually programmable and controllable, so that each motor inside the machine under test could be tested with suitable rotational speed, rotation direction and ramp signal.

Measurement data such as temperature, air pressure and rotational speed, from various sensors had to be sampled in order to compare the data to their target values.

An intuitive touch screen GUI should allow for well-directed configuration of testing scenarios and for adaption and parameterization of tests for special devices.

Implementation and challenge

Primary challenge was the integration of a great number of frequency converters being controlled individually and simultaneously in order to operate different numbers and types of motors, belonging to various engine-power classes. In this context, motor performance can reach rather high values up to 5.5 kW. The maximum rotational speed is about 5500 R/min-1.

In order to allow for ideal and ergonomic handling of the system, all hardware has been integrated into a Rittal TopPult. Frequency converters from Leroy Somer (Emmerson) have been chosen and are controlled by means of NI’s LabVIEW and an OPC server, which offers all required control options.

Frequency converters are designed for a maximum power of 5.5 kW and include a power supply, an Ethernet module, which is used for control and regulation, and an emergency shutdown for all motors to prevent mechanical damage.

The tester system comprises an ActiveX-Control-based, intuitive and configurable GUI that can be operated via touch panel. For control and regulation, the GUI is connected to the whole tester system via LabVIEW-based applications. The GUI allows for configuration of suitable rotational speeds, engine-power classes, ramp signals and number of motors controlled.

It is not only possible to control motors independently of each other but also to connect frequency converters to each other for mutual control. The LabVIEW application is running on an integrated panel PC, which is connected to frequency converters by means of a 24-prt Ethernet switch.

All measurement and control tasks are operated by a CompactDAQ chassis from National Instruments, which is equipped with several digital and analogue I/O cards. This system utilizes a USB connection for communication with the test stand application, which is running on the panel PC.


NOFFZ has designed a flexible test stand for Innovent, which allows for independent control of frequency converters for motors driving grinding gears and cutting units. The system also allows for data acquisition via bus systems from various sensors being integrated into the production line so that a regulated manufacturing process can be generated.

The system comprises an intuitive GUI allowing for complete configuration of testing scenarios according to any particular device under test without further programming. The basic idea ‘parameterization instead of programming’ has been realized for the customer’s benefit.

The next stage of expansion includes a Nano client and a 10“ touch screen, displaying an autonomous mobile LabVIEW application, allowing for comprehensive process control from any location.