Optional Extras

Optional Extras

We offer a large variety of optional extras as e.g. key-operators, padlockable handles, auxiliary contacts or enclosures. This allows us to meet the requirement of the world market.

One or more optional extras may be used in combination with any one switch provided they are of the same switch size. In some cases, for technical strength or esthetic reason, it may be desirable that a switch be combined with an optional feature of the next larger switch size.

Catalog 101: Optional Extras and Enclosures

Door clutches and padlock devices with integrated door clutch:

Door clutches are used to disconnect the handle or the padlock device from the switch when they are installed as base mounting or fitted in a large enclosure.



Auxiliary contacts:

Auxiliary contacts can be used as normally open (NO) or normally closed (NC) contacts.

Key-lock devices:

Key-lock devices are available for several locking programs. For master key locking systems please contact your local Kraus & Naimer sales office.


Padlock devices:

These additional devices are used to lock the handle in the 'OFF' position using one or more padlocks.

Shaft extensions:

Shaft extensions are used for switches with base mounting to compensate different mounting heights.

Protective covers:

The protective cover prevents accidental contact with current-carrying terminals.

Push-pull interlock:

Used to interlock the switch so that the handle can be rotated only when pushed or pulled. Auxiliary contacts can be operated by means of the axial movement of the handle.


Electro-mechanical interlock:

The electro-mechanical interlock locks the switch in any switching position. The interlock device is operated by energizing or de-energizing the electro-mechanical system. Adding auxiliary contacts to the switch permits the device to be operated in pre-determined positions.


Electro-mechanical trip device (Undervoltage release):

The device consists of a magnetic system which releases the switch to the trip position at voltage failure or undervoltage (70% nominal voltage) and thus prevents the machine from restarting automatically.



Isolating Enclosures:

Isolating enclosures are available either as a highly UV-resistant design as well as for applications in an aggressive environment, such as oil, chemical substances, and grease. All variants are offered with cover coupling with or without cover interlock, strong durable plastic and increased wiring space.