Understanding machine safety

Schmersal serial diagnostics

In a traditional safety system, a faulty device or sensor can lead to significant loss of production. Schmersal’s Serial Diagnostic (SD) technology was designed minimise such downtime while also decreasing installation costs.

SD capable sensors and interlocks can be connected in series which saves on physical wiring and labour costs while adding comprehensive status and diagnostics data, making finding faults faster. The data from both electronic safety sensors and interlocks with SD interface can be processed by a Schmersal PROTECT PSC1 safety controller or made available to a supervisory system via one of its many industrial safety busses such as ProfiNet, EthernetIP, Modbus, EtherCat, ProfiBus & CANopen. SD systems are also able to achieve the highest Performance Level, PLe.

Mixed installation of electronic safety sensors and interlocks to form a safety function can be realised easily in the field with the SD interface. The actuating and diagnostics data are transferred in the SD interface, which are connected in series via one wire between the SD gateway and the SD slave. Communication with up to 31 slaves per SD gateway is possible. These can also be divided into several different safety functions as required.

Devices can be installed via SD Junction boxes, Passive Field Box (PFB) or Passive Distribution Module (PDM). The installation system with SD junction box enables quick wiring between safety switchgear devices. The cables with M12 connectors are routed directly from one safety switchgear device to the next and can be routed in the cable channel with SD junction boxes.

The passive field box PFB allows switchgear devices to be connected to a central point in the field. The passive distribution module allows the safety switchgear devices to be wired into a single switch cabinet via spring cage clamps.

PSC1 with integrated SD gateway

By Anthony Zahra - APPLICATION ENGINEER TÜV Nord, CSME, FS ENG (TÜV RHEINLAND, #3296/11, SIS)

With over 20 years of experience in various areas in safety, electrical and automation, Application Engineer Anthony Zahra holds a TUV certification, as well as training several courses at Control Logic that include Emerson, Red Lion and others. Book an appointment with Anthony or one of our other accredited TUV engineers by calling Control Logic on 1800 557 705.