Dead Sea conveyor given a new lease of life

We were challenged with upgrading an existing VSD & automation system which controls an 18km long transport conveyor taking potash from its source in the Dead Sea to a processing area. The customer is one of the world’s largest suppliers of potash products, mainly in the cosmetic industry.

The conveying plant wanted to keep its two existing brushless synchronous motors and upgrade the vsds with new frequency converters and field excitation drives.

The project team chose Siemens Sinamics AFE drives because these converters could be easily adapted to the existing motors, as well as installed, and to some extent tested, during operation.

 

Our Solution

Two off Siemens Sinamics drives were used to control the existing synchronous motors, communicating via profinet to a new S7-300. Each low voltage synchronous motor has a dual wound stator and separate exciter drive, which are controlled by the same S7-300 via Profibus.

The two motors load share with one S120 being the master controller. Each S120 consists of a low harmonic fully regenerative AFE front end with a motor module on each of the existing motors’ winding.

An S7-400H system was used for the brake, lubrication and tension control of the conveyor, with ET200M remote IO communicating on profinet. Once installed, this PLC can be added to and at a later date take over from the existing plant’s old higher level PLC system.

 

Results

• Increased productivity
• Reduced machinery downtime
• Lower manual intervention

 

Client Feedback

Minimising costly plant standstills and the time-consuming transport of potash by road, our client was highly satisfied with the result, not only from the technical, but also from the logistical point of view.