PD IEC/TS 61496-4-2:2014 - Page 2

Safety of machinery. Electro-sensitive protective equipment. Particular requirements for equipment using vision based protective devices (VBPD). Additional requirements when using reference pattern techniques (VBPDPP) | Status: Superseded, Withdrawn

1 Scope Replacement: This part of IEC 61496 specifies requirements for the design, construction and testing of electro-sensitive protective equipment (ESPE) designed specifically to detect persons as part of a safety-related system, employing vision-based protective devices (VBPDs) using passive reference patterns (VBPDPP) for the sensing function. Special attention is directed to features which ensure that an appropriate safety-related performance is achieved. An ESPE may include optional safety-related functions, the requirements for which are given in Annex A of IEC 61496‑1:2012 and this Technical Specification. This part of IEC 61496 does not specify the dimensions or configurations of the detection zone and its disposition in relation to hazardous parts for any particular application, nor what constitutes a hazardous state of any machine. It is restricted to the functioning of the ESPE and how it interfaces with the machine. A VBPDPP is defined as consisting of a single image-sensing device viewing on a passive reference pattern as the background and where the detection principle is based on blocking or partially preventing the view of the pattern. Information about the thickness, shape, surface characteristics or location of the object is not required for detection. For multi-image sensing devices, additional techniques, requirements and test procedures can be necessary.

• • This part of IEC 61496 is limited to automatic vision-based ESPEs that do not require human intervention for detection.
• • It is limited to automatic vision-based ESPEs that detect objects entering into, or are present in, a detection zone(s).
• • It is limited to ESPEs using active illumination technique
• • Excluded from this technical specfication are VBPDPPs employing radiation at wavelengths outside the range 400 nm to 1 500 nm.
• • This document does not address those aspects required for complex classification or differentiation of the object detected.

This part of IEC 61496 is relevant for VBPDPPs having a stated detection capability up to 200 mm.

NOTE The positioning of VBPD in respect of parts of the human body is presented in Annex AA of this technical specification.

This part of IEC 61496 does not deal with EMC emission requirements.