Page 7 - Industrial Terchnology EXTA 22nd March 2021

assessment of the ambient conditions with proof Safety laser scanner field sets
tests if unsure.
scanner is working at fast speeds and short time
6. Configure safe switching of field sets differences and therefore a statistical error must be
One of the great advantages of safety laser scanners taken into account. For example, for the Sick
is the ability to configure field sets, and store and microScan3, we recommend that a space of
select different fields. The safety function (as per EN approximately 65 mm is ensured, for example from
ISO 13849/EN 62061) for selecting the field set a wall, to maximise availability. Scanners may well
should normally have the same safety robustness work ‘most of the time’ below these recommended
(PL/SIL) as the scanner itself, but sometimes, the values but will trip randomly. Check the tolerance
safety of the mode selection is overlooked. For ban of the scanner that you are intending to use,
example, if a standard PLC or a single channel limit which can be up to 100 mm in some cases.
switch is used for selecting a field set, this would The aspiration of productive availability is the
reduce the PL/SIL of the whole system to possibly starting point for any well installed and easy-to-
PLc or even PLb. control safety installation. But, especially if you are
An incorrect selection of field set could mean new to the technology, then it is a good idea to
that an AGV is operating with a small protective contact the manufacturer for advice to avoid the
field in combination with a high speed and, hence, potential for unsafe installations. Sick’s family of
long stopping time, creating a hazardous situation. safety laser scanners offers a solution for every
mobile and stationary application and we’re always
7. Leave space close to perimeters ready to answer questions. We can also offer
It would be easy to assume that a protective field complementary support, engineering, safety
should be drawn as close as possible to the concept and safety verification services.
perimeters of the area to be protected. However, the www.sick.co.uk

March 2021 • INDUSTRIAL TECHNOLOGY EXTRA • p7