Page 62 - MACHINE TOOLS WORLD - DECEMBER 2021

TECH INNOVATION

Danger spotted, danger averted
SAFETY SOLUTIONS

to prevent unexpected start-up

Companies repeatedly have to contend with serious, even fatal, accidents caused by the unexpected or
unseen start-up of complex machinery and systems.

isks due to the unexpected start-up or restart of requirements that must be considered. In addition, it also lays
hazardous movements exist in accessible machinery down design safety measures that seek to prevent unexpected
Rareas or if protective devices can be can be bypassed start-up in order to allow safe intervention by people in
and people are present in those areas without being noticed hazardous areas.
– perhaps on account of maintenance or repair work. These risks The standard refers to unexpected start-up due to all types
need to be determined as part of a risk assessment, which every of energy, i.e. energy supply (electrical, hydraulic, pneumatic),
machinery manufacturer or system integrator must carry out stored energy (gravity, tensioned springs), which is often
and document under the Machinery Directive. overlooked, and other external influences (wind).
The particular problems that this topic presents were the The following presents some example safety solutions on
reason for a dedicated harmonised standard – EN 1037 the topic, all of which are available in the range provided by
‘Prevention of unexpected start-up’, the successor standard to Schmersal.
which has been published as EN ISO 14118:2018.
Versions of the stop command
EN ISO 14118:2018: Prevention of unexpected In the following, it is assumed that a stop command is safely
start-up generated by a protective device being triggered in the input,
The standard offers an overview of a range of aspects and logic and output chain with the necessary performance level

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