Safemaster STS – The key to more safety

Don‘t you wish you had a simple safety switch and trapped key interlock system to protect your dangerous working areas. If you are looking for a reliable, expandable, flexible and cost saving solution, then you have found the perfect product with our TÜV-approved system SAFEMASTER STS.

The SAFEMASTER STS Program consists of modules that can be individually combined and adapted to your application. They combine the advantages of safety switches, interlocks and key transfer in one system. The modular design allows systems to be assembled out of several units, or to modify and expand existing systems as required. All mechanical interlocks can be utilised in machine and plant concepts without wiring. They provide an economic and reliable proctection in wide applications.

With only a few single components, a number of individual interlock units can be assembled. The stainless steel units guarantee good stability. Extensive equipment allows a simple mounting.

Advantages and customer benefits:


  • Combines advantages of safety switch, solenoid lock, trapped key interlock and
  • command function in one System
  • EC type approval certificate in accordance with the statutory requirements
  • For safety applications up to Cat. 4 / PL e according to EN ISO 13849-1 as
  • individual system
  • Modular and expandable system
  • Version available in plastic as well as a in rugged stainless steel
  • Wireless safeguarding
  • Easy installation through comprehensive accessories
  • Protection against lock-in
  • Fault exclusion is not required

Safety switch and trapped key interlock system




The system offers maximum safety and respects the requirements of the user concerning robustness, long life and user ergonomics. Special features are stainless steel units with ergonomic linear keys. It is flexible, can be easily extended and guarantees a safe and interruption free process, offering an intelligent and cost saving solution for industrial applications of all kinds.


Suitable industries:


  • Automation technology
  • Stone and cement processing
  • Recycling
  • Steel, wood and foodstuff industry
  • Conveyor technology and logistics
  • Railway and automotive industries


Application example:


The image shows a part of the palletizing system with three access points. When opening the main access door A during operation, the machine stops immediately. To open the service doors B or C, one proceeds as follows: Remove the key A, insert the key on door B, remove the second key, open the door B. The machine can be restarted in the reverse sequence.

Your advantage: Maintenance door B is secured without wiring and the key serves as a protection against unexpected start-up of the plant. Plastic units can be easily combined with the stainless steel version, for example in the outdoor area of a plant.

DOLD : STS unit
DOLD: STS safemaster applicatie