Key-In-Pocket System

The new maintenance safeguarding “key-in-pocket” system from Pilz protects unauthorized machine restart, allowing maintenance work to be carried out safely. Digital maintenance safeguarding is based on the access permission system PITreader and guarantees safety and industrial security as only authorized personnel can access the plant or machine during the maintenance process.

Larger plants often have a number of danger zones, which are protected using safety fences. This places demands on safety and it is important that only authorized personnel have access for maintenance work. At the same time, it is essential to ensure that nobody is left in the danger zone when the plant restarts.

With “Key-in-pocket,” Pilz has created a digital maintenance safeguarding system which is flexible to meets the demands of both safety and industrial security. “Key-in-pocket” ensures that the machine does not restart while maintenance work is being done and that unauthorized personnel do not gain access. The solution offers safety in the face of a hazardous restart while at the same time, industrial security, because it is impossible to tamper with the maintenance work.

The system is based on the access permission system PITreader and is implemented using the configurable small controller PNOZmulti 2 or the automation system PSS 4000. Users are given an RFID key with their individual permissions, which can be read on the safety gate using PITreader. This way, one or more users who are authorized for maintenance work can authenticate themselves. At all times, the operator knows who has access for which task. Temporary permissions can also be assigned.

After successful authentication, a personalized security ID is stored for the user in the controller and is kept in a safe list. The machine can now be shut down, the safety gate opened, and the machine accessed. During this time, the RFID keys remain with the respective users.

“Key-in-pocket.” Once maintenance is complete and people have left the danger zone, everyone signs out. The security IDs are removed from the safe list on the Pilz controller, and the machine can be restarted.

Digital maintenance safeguarding is specifically designed for machines with danger zones that are protected via safety fences. It offers an economical, efficient alternative to mechanical lockout-tagout maintenance safeguarding systems, which are attached to all safety gates. As it is possible to enter or leave the plant via various safety gates, “Key-in-pocket” offers staff greater flexibility and thus saves time during maintenance.