Each industry has its specific needs when it comes to process control instrumentation. Whether considering petrochemicals, general mechanical engineering or ship building, the requirements vary in terms of fundamental physical properties, preferred materials and supplementary factors such as cable standards.

When using magnetic level indication (Visual Level Indicator – VLI) for liquids, certain demands have to be met. By adding electrical accessories such as magnetic switches or/and level transmitters, a VLI can be upgraded to become a fully inclusive system. This can be used as an actuator for pump and valve actions as well as analysing points within an SPS or computer system. Aside from the choice of materials and adherence to specific standards, the electrical connection is another key factor.

Integrated cables of 3m, 5m, 10m and 20m length are typically sufficient to connect to a junction box or a circuit branch. However it is difficult to find a common cable for all requested requirements. Halogen free or chemical resistance are just a couple of demands made on suppliers as are the temperature range and type of shielding. In order to create a universal interface which allows the customer to use his own cables, WEKA has launched a new magnetic switch series using M12 plug-connectors. The M12 thread is manufactured according to IEC 61076-2-101 and is readily available worldwide. This design accommodates a straight or angled mating plug, mounted to the customer’s cable. Alternatively a cable with injection-moulded mating plugs can be used.

The M12 Magnetic Switch is lower in price than its cable-using counterparts. It is easy to install and to swap out when replacing. Other features are the M12’s high loading capacity and extremely robust stainless-steel casing. Each VLI can be upgraded with any kind of magnetic switch even if the level indicator has been in use for decades.