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Reliable energy generation


The customer

The PRAMAC Group of Siena develops, manufactures and sells a wide range of generators (1 kW to 3 MW) all over the world. ABB OTM motorized change-over switches disconnectors are used in the Load Transfer Solution (LTS) network switchboards, which are supplied separately with external logic.  

The complete system, consisting of a control panel and an LTS network switchboard, supervises the distribution network and automatically starts the motor when a problem occurs, so that within a few seconds the load is powered by the generator.

The challenge

It is extremely important that the operation of the generators has a high level of safety and reliability. The transfer devices need to ensure reliable operation all circumstances and prevent any risks for personnel and equipment.

Since PRAMAC is present globally, it also requires a supplier that is able to provide pre- and aftersale support in all contexts where their generators are used, wherever they are used.

The ABB solution

A crucial factor that made PRAMAC choose ABB OTM motorized change-over switches was the presence of the double sectioning solution. This guarantees higher levels of protection against the risk of electric arcs that are disconnected in two points instead of one. This prevents the contacts from sticking and creating risks for equipment and personnel.

Another important advantage was that OTM motorized change-over switches have an intermediate stable       0 position. This technical feature makes it possible to disconnect from the network when necessary– even during the starting phase preceding generator connection.

Other factors were the completeness of the OTM range, specifically designed for use with generators. OTMs are produced in a way that minimizes the micro-recoils of the contacts during the operation phase. This improves the reliability significantly and prevents the creation of electric arcs and risks of accidents.

Last but not least, the compactness was also an advantage. The compact and smart design of OTM switches has allowed PRAMAC to reduce the size of their panels.



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