Keba Kemro KeTop T10, Руководство по проектированию устройства

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The emergency stop button may not, therefore, serve as the primary safety
device but is provided exclusively to cover any residual risks.
Instead of this and depending on the mode of operation, other methods should
be employed as the primary safety device, for example guards, light barriers
and two-hand control devices or enabling control devices.
When the emergency stop button is activated, the entire machine or all of the
machines that are switched together in a plant must be lead to a safe state e.g.
by stopping and switching off the power to the endangering drive mechanisms
(stop categories 0 or 1 in accordance with EN 60204-1).
The release of the emergency stop button must not cause any uncontrolled
restart of the machine.
Irrespective of whether a handheld terminal has an emergency stop button or
not, permanently installed, universally identifiable and easily accessible emer-
gency stop buttons must be provided at selected points around the machine
in every case.
17.9 Application of Emergency Stop Button and Stop Button on the
Handheld Terminal
The Machinery Directive does not specify any detailed requirements in respect
to the colouring of the operating elements for emergency stop. The require-
ment states: “The device must have clearly identifiable, clearly visible and
quickly accessible controls“.
Emergency stop buttons are usually identified by red/yellow. The specific de-
sign should have a signalling function whose effect is that any person, and
especially untrained people, can quickly recognise the control as the device to
eliminate a hazard in the case of an emergency.
One imperative requirement for equipment identified in this way is, therefore,
that it must be possible to trigger a safe state at any time and in any operating
mode, without further knowledge of the machine (see also EN ISO 13850).
It is not acceptable for an emergency stop button to be enabled temporarily,
since this can lead to faulty operation and life threatening loss of time in panic
situations.
If one considers handheld terminals in relation to these requirements it is evi-
dent that a differentiation must be made as to whether an emergency stop
button on the handheld terminal may be used or not, depending on specific
criteria and applications.
Permanently installed handheld terminals: Emergency stop button
Permanently installed handheld terminals are provided with a cable by means
of which the handheld terminal is connected to the designated machine. The
handheld terminal is usually connected to or disconnected from the machine
with the machine switched off. This takes place during the installation or de-
KeTop T10 Appendix: Machinery Safety
© KEBA 2014
Project engineering manual V1.02 67