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Glossary
Dangerous state
A dangerous state is a status of the machine or facility, where
people may be injured. Protective devices prevent this risk if the
machine is operated within its intended use.
The figures in this document always show the dangerous state of
the machine as movement of a machine part. In practice, there
are different dangerous states, such as:
•
Machine movements
•
Electrical parts
•
Visible and invisible beam
•
A combination of multiple hazards
EDM
External device monitoring
Enabling device
Additional manually operated device used in conjunction with a
start control and which, when continuously actuated, allows a
machine to function. (EN ISO 12100)
External device monitoring
The external device monitoring (EDM) monitors the status of down‐
stream contactors.
In order to use external device monitoring, positively guided con‐
tactors must be used to switch off the machine. If the auxiliary
contacts of the positively guided contactors are connected to the
external device monitoring, the external device monitoring checks
whether the contactors switch correctly when the OSSDs are
switched off.
Hazardous area
Hazardous area is any space within and/or around machinery in
which a person can be exposed to a hazard. (ISO 12100)
OSSD
Output signal switching device: signal output for the protective
device, which is used for stopping the dangerous movement.
An OSSD is a safety switching output. The functionality of each
OSSD is tested periodically. OSSDs are always connected in pairs
and must undergo dual-channel analysis for safety reasons. An
OSSD pair is formed from 2 OSSDs that are connected and ana‐
lyzed together.
Protective field
The protective field protects the hazardous area of a machine or
vehicle. As soon as the electro-sensitive protective device detects
an object in the protective field, it switches the associated safety
outputs to the OFF state. This signal can be passed to controllers
resulting in the dangerous state coming to an end, e.g. to stop the
machine or the vehicle.
A horizontal or vertical protective field is required, depending on
the application. The electro-sensitive protective device can there‐
fore be mounted in horizontal or vertical alignment, depending on
the requirements.
Protective stop
Type of interruption of operation that allows a cessation of motion
for safeguarding purposes and which retains the program logic to
facilitate a restart. (ISO 10218-1)
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GLOSSARY
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O P E R A T I N G I N S T R U C T I O N S | nanoScan3 Tool - URCap
8025720/1A9R/2020-12-15 | SICK
Subject to change without notice
