Siemens Automation and Drives has developed a new range of ultrasound proximity switches for the Ex area. The contact-free Simatic PXS810 sensors are available in M18 compact design and in M30 K3 with fixed sensor head. The M18 types are designed for sensing ranges 5-30cm and 15-100cm, whilst the M30 K3 types cover ranges from 6-30cm and a maximum of 60-600cm. The sensors can each be operated as diffuse sensors, retro-reflective sensors or thru-beam sensors and are suitable for use in areas such as paint shops, woodworking and food processing.