Bosch REXROTH IndraControl VEH 30.2, Руководство по планированию проекта

Страница: 40 / 112

Notes on the "emergency stop"
button
● In theory, a perfectly designed machine should not require an emergen‐
cy stop pushbutton, because the Machinery Directive demands that a
machine must be safe throughout its lifetime and in all operation modes.
In practice, however, one is aware that unforeseen situations arise, in
spite of all precautions.
In order to enable a fast stopping of the machine in these cases, or to
avert danger, an emergency stop button is provided on most machines.
The following figure shows that, a machine is permanently in the hazard
state from the viewpoint of the emergency stop button, for as long as
this button is not activated.
Fig.4-2: Emergency stop button in neutral position (not pressed)
Fig.4-3: Emergency stop button pressed
● Therefore the emergency stop button must not serve as the primary
safety device, but is provided exclusively to cover any residual risks.
Instead of this and depending on the operation mode, other methods
should be employed as the primary safety device, for example guards,
light barriers and two-hand control devices or enabling devices.
When the emergency stop pushbutton 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 en‐
dangering drive mechanisms (stop categories 0 or 1 according to EN
60204-1).
The release of the emergency stop button must not cause any uncon‐
trolled restart of the machine.
Irrespective of whether a hand-held terminal features an emergency
stop pushbutton or not, permanently installed, universally identifiable
and easily accessible emergency stop pushbuttons must be provided at
selected points around the machine in every case.
Bosch Rexroth AG DOK-SUPPL*-VEH*30.2***-PR03-EN-P
Rexroth IndraControl VEH 30.2 Hand-Held Terminal
38/109
Technical Data