Festo CDSA-D3-RV, Руководство по эксплуатации

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In contrast to the emergency stop switch or stop switch, a machine in the special operating modes
with 3-position enabling switch is always in the safe state as long as it is not actuated.
1 "Normal position" (3-position enabling
switch not actuated)
2 "Approval" (3-position enabling switch
pressed)
3 "Panic" (3-position enabling switch strongly
pressed)
Fig. 29 Enabling functions
The enabling function is also described in EN 60204-1 and corresponds to the state of the art.
The panic setting of the 3-position enabling switch was introduced because people in shock situations
often react with a reflex-like cramping of the limbs and cannot release the 3-position enabling switch.
For this reason, pressing the 3-position enabling switch firmly also results in switch-off.
The controller must be designed so that the movement is not initiated directly with the activation of
the 3-position enabling switch, but only through the additional actuation of a control button. They may
be membrane keys on the handheld terminal or graphical software keys on the touchscreen.
An optionally available joystick can also be used to trigger the motion signal.
Only stop categories 0 or 1 are permitted for the enabling function in accordance with EN 60204,
which means that the drives must be shut down in every case with a stop by the 3-position enabling
switch.
In order to prevent improper permanent actuation of the 3-position enabling switch by mechanical
locking devices, the recommendation is to limit the maximum duration of an accepted approval. This
must be achieved by means of a controller downstream of the handheld terminal.
A 3-position enabling switch is not a substitute for a two-hand circuit, which is specified for some
machines (e.g. presses), and must therefore not be confused with it.
In contrast to the 3-position enabling switch, the two-hand control forces the endangered limbs of the
operating personnel into a safe position during machine movement.
15 Appendix: Electromagnetic compatibility
Directive 2014/30/EU of the European Union requires the member states to harmonise their legisla-
tion on electromagnetic compatibility. In the following text, this directive is referred to briefly as EMC
Directive.
Appendix: Electromagnetic compatibility
57 Festo — CDSA-D3-RV — 2020-08