Restart Interlock Per En 1037:1995 (Safety Of Machinery - Prevention Of Unexpected Startup) - B&R Mobile Panel 40 User Manual

In this regard, it is important to note that in category 3 and later, single faults must be detected promptly in order
to prevent an accumulation of faults, which could then lead to a loss of the
In electrical and electronic systems, faults that must be detected include cross faults between circuits, interruptions,
short circuits or stuck contacts. Specially certified
faults in the individual safety
if the connection with the corresponding circuits has also been implemented for the respective PL in accordance
with the product description and the PL of all components contributing to the
account.
The PL for an overall safety
ules.
Standard EN ISO 13849-1 provides guidelines for more easily determining the PL for a
of multiple components.
Note that with safety components connected in series, the PL of the
component with the lowest PL in the
with category 4 PL e, category 3 PL d and category 2 PL c would result in a performance level of PL c for the
overall safety function. Further note that a fault would result in the loss of the
4 PL e components are integrated in the
only category 2.
Combining several PLs
A FMEA (failure mode and effects analysis)
is done by theoretically, or even practically, running through all possible faults and showing that the requirements
of the category are sufficiently fulfilled.
5.4.6 Restart interlock per
up)
Keeping a machine in a state of rest while personnel are working in the danger zone is one of the most important
requirements for safely operating machines.
Startup refers to the transition of a
unexpected if caused by one of the following:
• A startup command generated due to
• A startup command generated due to incorrect operation of a startup
the machine.
• Restoration of the power supply after an interruption.
• External/Internal influences on parts of the machine.
To prevent unexpected startup of machines or parts of machines, power should be removed and dissipated. If this
is not practical (e.g. frequent brief interventions in danger zones), other measures must be taken:
• Measures to prevent randomly generated startup commands.
• Measures to prevent randomly generated startup commands from causing unexpected startup.
• Measures to automatically stop the dangerous part of the
caused by unexpected startup.
Mobile Panel 40/50 User's manual V1.80
circuits. The overall PL necessary for the
function must therefore always be calculated from the individual components or mod-
safety function. For example, a
safety
can reduce the overall PL.
can ensure that a fault will not lead to the loss of the
EN 1037:1995 (Safety
machine or its parts from a state of rest to a moving state. A startup is considered
controller failure
safety relays with their own specific PL are often used for detecting
safety
safety
safety
function. This is because one of the components being used is
of machinery - Prevention of unexpected start-
or external influences on the controller.
machine
Standards and certifications
safety function.
function is only achieved, however,
safety function have been taken into
safety function consisting
function is determined by the
function consisting of 3 components
safety function even though category
safety
control actuator or another part of
before a dangerous situation
safety
function. This
can be
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