What is Alfred?


A range of robust, heavy duty interlocking devices designed and certified to be used in hazardous locations and explosive atmospheres.


These mechanical and electromechanical interlocks are suitable for industries where combustible dusts or flammable gases may be present.


With ATEX, IECEx, UKEx, CCCEx and North American HazLoc certificates, the range includes solenoid interlocks and switch interlocks suitable for use up to Zone 1 (Gas) and Zone 21 (Dust), and atmosphere ignition temperatures of above 85°C. 


Made of tough stainless-steel enclosures and with an IP69 rating, Alfred is perfect for any harsh dusty environment.

Main features of the Alfred range


An Alfred interlock can be configured from a selection of actuators (including an escape release) and head modules, and can include up to three key adaptors which can all be mounted above an ex rated switch module or an ex rated solenoid module. These features make Alfred the most customisable Ex interlock on the market.


✅ Robust, made of 316 stainless steel and with a retention force of 7kN

✅ Highly customizable, with possibility to include guard locking, trapped keys, and escape release

✅ Third-party approved, with ATEX, IECEx, UKEX, CCCEx, North American HazLoc certificates

✅ Certified for use in zone 1 (gas) and zone 21 (dust) allowing the interlocks to be close to the machine

✅ IP69 rated

A Fortress representative can help configure a solution to the exact requirements of your application.


These exact requirements can usually be defined by discussing with one of the Fortress team experts. Since this is an interlock for explosive atmospheres, we will need to know the specifications of the install locations from your risk assessment.


To find out more check out the Alfred brochure below. In alternative our application experts are always happy to help select the right solution. Contact us to start the process.

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