Safe Operation - Interlocks for an interlock and key locking system _ DOLD

Over the past 80 years, DOLD has developed into a specialist in the fields of switching relays, machine safety and control technology.

Some of DOLD's products, the DOLD Safemaster STS interlock system, provides a solution in the event of containment hazards, such as in a freezing cell, and prevents a machine from starting up while a technician is working on it, for example.

The interlock system with safety category PLe

The safety of employees and machinery in a hazardous area must always come first. Especially if employees have to enter the hazardous area. With the installation of an interlock system you protect dangerous work areas from unwanted or uncontrolled access.

Mechanical system

One of the advantages of the DOLD Safemaster STS interlock system is that it is largely mechanical. The main module is wired, but the individual interlocks do not need to be wired. This saves on cabling costs and still ensures a safe situation. The unique mechanically coded keys and key release allow you to enforce a key sequence. Users are thus forced to follow a certain sequence for maximum (machine) safety.

No additional fault exclusion necessary

Dold Safemaster STS is the only interlock system with safety category PLe. This is because it is a mechanical interlock system. A normal interlock system has safety category PLc. With an additional safety switch, it is possible to achieve safety category PLd. The additional safety switch serves as a fault lockout. A normal interlock system is a single-channel safety system. Adding an additional safety switch creates a two-channel safety system.

Key transfer system or key transfer system

The basic principle of the key transfer system or transfer system is that a machine or plant is in a secure state before anyone can gain access to the hazardous area. Another safety aspect is that a key is inserted into a safety switch or used to open a door lock. This can be used to enforce a particular operating sequence that cannot be deviated from. As a result, a high level of security is achieved and a wide variety of hazardous areas can be protected.

The modular key transfer system or transfer system has modules equipped with illuminated (emergency) buttons, but these are not required for setting up a key transfer system.

Containment protection with Interlock system

DOLD's Safemaster STS interlock system can also be used to prevent entrapment of employees. For example, in the food industry. To ensure that food remains fresh for a long(er) time, it is often frozen within a foreseeable time after processing. This is done in huge spiral freezers, which can reach temperatures as low as -40°C. Above all else, an employee must be prevented from being trapped in such a cold environment. The safety of employees is paramount and must be guaranteed. By using the Safemaster STS interlock system, the entrances to the freezers are protected against unintentional entrapment.

Want to see how this system works and where it can be applied? Check out our website for several videos https://fortop.nl/solutions/producten/interlock-systeem-beveiliging-dold-safemaster-sts/  and application examples Interlock system - Reliable even under freezing conditions