Filling weight control for the FEC Series
In free fall

Weight measurement could not be more space-saving and precise: Together with visiotec, the inline control specialist from Uhlmann Pac-systeme, Fette Compacting has developed the NMC sensor for the capsule filling machines of the FEC Series. The system measures the weight of pellets without touching them.

Fette Compacting uses numerous revolutionary technologies in the capsule filling machines of the FEC Series. These include the NMC sensor, which the company developed together with visiotec from Uhlmann Pac-systeme GmbH. The special feature: The sensor records the weight of pellets as they fall. It measures milligrams in milliseconds – and in an entirely contactless manner, which is unique. The NMC sensor is fully integrated and can even record complex and dynamic processes ultra-precisely with a sampling rate of four Kilohertz.

Unlike a conventional weighing system, the NMC sensor requires significantly less space. It doesn’t display any transient response and it delivers net measurements. This distinguishes it from standard scales which only deliver gross measurements, i.e. including the capsule shell.

The specialists of visiotec adapted the sensor perfectly to the capsule filling machines offered by Fette Compacting. Engineers at both companies cooperated on the proof of concept, integration in the existing FEC Series system and installation of the sensor.

Easy integration and high precision

The decisive factors in the development of the sensor entailed easy integration in the machine and a high degree of precision. Furthermore, it transpired at an early stage of collaboration that the sensor would need to be easily replaceable to guarantee a high degree of user friendliness, thereby facilitating cleaning of the machine, for example.

That is why we equipped it with a housing which is particularly suitable for pharmaceutical applications. The material, design and sealing concept prevent ingress by dust and particles while also ensuring that the sensor can be easily cleaned.

Precise recording of the net weight
Net Mass Control (NMC) – Sensor for precise and efficient measurement of net weight of pellets. Detail view FEC20 with one pellet station and one NMC sensor (highlighted).

Non-contact measuring principle
The technology is based on a contactless capacitive measuring principle: pellets are moved through an electric measuring field. The sensor records the change of the field over time.

The signal-time curve
A signal-time curve results from the measurement. The integral of the area under this curve can be used to determine the exact metered quantity.