// Press release
The data bus standard »Dupline« was developed especially for rough applications and long distances. It is well suited to fields such as mining, extraction operation and tunnel advance – and has the added advantage of being able to switch on safety switchgear using the »Dupline-Safe« standard, transmitted via the same bus conductor as the non-safety signals.
At the SPS/IPC/DRIVES, steute will be presenting a series of robust switchgear which can comfortably be switched on via Dupline and which can be integrated into safety networks via DuplineSafe. The series comprises the emergency pull-wire switches ZS 75 and (in Ex design for mining industry) EEx ZS 75 Mining, also available as turning lever switches, belt-alignment switches and as emergency stop switches with different actuators.
The devices can easily be installed »on the job« since only the unshielded two-core cable has to be connected and the addressing is taken care of by hand-held programming. Thus, the operator is flexible and able to perform extensions or conversions very quickly, with the operating voltage also being controlled by the bus conductor.
The active principle behind the DuplineSafe standard is simple: the input module integrated in the switchgear transmits a constant signal. Any change to the signal, e.g. actuation of the emergency-stop signal or a fault in the signal transmission, leads to actuation of the output relay. This guarantees very immune, reliable signal processing. Up to 63 input modules can be connected to each channel generator.
With these features, the DuplineSafe system is suitable for the actuation of robust safety switchgear working under less than favourable ambient conditions. steute has, of course, selected switchgear to suit. The ZS 75 series enclosure is made of die-cast zinc and both the actuators and switch inserts are designed to survive more than one million switching cycles. The explosion-proof variant of the EEx ZS 75 Mining is ideally suited to applications in underground mining of equipment category M1. The safety bus standard meets the requirements of SIL 3 according to IEC EN 61508.
