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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
Demand rate
The demand rate refers to the number of events in a specified
time period that trigger the safety function of a safety-related
component.
EDM
External device monitoring
Electro-sensitive protective
device
An electro-sensitive protective device is a device or system of
devices for safety-related detection of people or parts of the body.
It is used to protect people from machines and facilities that pose
a risk of injury. It triggers the machine or facility to adopt a safe
state before a person is exposed to a hazardous situation.
Examples include safety light curtains and safety laser scanners.
ESPE
Electro-sensitive protective device
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.
Field set
A field set consists of one or more fields. The fields in a field set
are monitored simultaneously.
A field set can contain different field types, e.g., a protective field
and a warning field.
Hazardous area
Hazardous area is any space within and/or around machinery in
which a person can be exposed to a hazard. (ISO 12100)
Master
The master device actively builds data connections in a network.
A device in a network which is addressed by a master device has
the role of slave.
In some modern networks, many or all devices can switch
between roles or have both roles at one time.
Monitoring case
A monitoring case indicates the machine status to the sensor.
Generally, one field set is assigned to each monitoring case.
The sensor receives a defined signal for the current machine
status. When a signal change occurs, the sensor activates the
monitoring case and thereby the field set that is associated with
the new machine status.
NFC
Near field communication. International transmission standard for
the contactless exchange of data by electromagnetic induction.
GLOSSARY
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