The Alfred range are robust, heavy duty interlocking devices which can be used to provide safe access and control for a variety of machinery for use in hazardous locations and explosive atmospheres.

The Alfred range has been designed and certified to be used in explosive atmosphere and hazardous locations. The Alfred range has ATEX, IECEx, UKEx, CCCEx and North American HazLoc certificates. The range includes solenoid interlocks and switch interlocks suitable for up to Zone 1 (Gas) and Zone 21 (Dust) and atmosphere ignition temperatures of above 85°C. As well as non-electric trapped key interlocks that are suitable for any explosive atmosphere or hazardous location.

An Alfred interlock can be configured from a selection of actuator modules (including an escape release possible in conjunction with the ex switch module), head modules and can include up to three key adaptors these can all be mounted above an ex rated switch module or an ex rated solenoid module. Making Alfred the most customisable Ex interlock on the market.

The Alfred range is very robust, made of tough stainless-steel enclosures with a head retention of 7,000N. With an additional IP69 certificate, the sealing protection makes Alfred is perfect for any harsh dusty environment and heavy duty or regular wash-down application

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Key benefits

Third party certified

The most customisable solutions

Highly robust

  • 3rd Party Approved (ATEX, IECEx, UKEX, CCCEx, North American HazLoc certificates and IP69) allowing Alfred to be used for applications in explosive atmospheres and hazardous locations
  • Certified for use in zone 1 (gas) and zone 21 (dust) allowing the interlocks to be close to the machine
  • Robust design results in only a single device being required to achieve the highest safety performance levels
  • Most configurable Ex interlock allows functionality to be specified to the exact application’s requirements
  • Suitable for zone 1/ zone 21 and division 2
  • Maximum surface temperature T6 / 85°C
  • Ambient temperature rate
  • Suitable for applications up to SIL3 Cat.4 PLe
  • Non-solenoid and solenoid interlock options
  • 24V
  • High actuator retention forces of 7,000N
  • IP67 & IP69
  • Escape release modules can be added to configurations
  • Wide range of actuators for all door types and ergonomic options
  • 316 stainless steel construction

A Fortress representative can help configure a solution to the exact requirements of an application. Engage us to work together on a project.

With the ability to incorporate control directly into the safety device separate elements of a control system can be combined into an interlock to offer an installation saving.

Fortress’ value is in providing custom solutions that fit the exact needs of the user – this can be through specific functionality.

These exact requirements can usually be defined by submitting a scope or having a call with one of the Fortress team. Due to this being an interlock for an explosive atmosphere, we will need to know the specifications of the install locations from your risk assessment. Contact us to start the process.

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Access control in manufacturing

Fortress offers the ability to control who can access industrial equipment safely alongside when they can access safely. Data of who, when and where from access events is collated for efficiency analysis.