Emergency Stop - Siemens SIMATIC ET200SP Function Manual

Circuit diagram example
4.2 Operating principle
4.2.2

Emergency stop

The emergency stop command device is a component that is widely used to protect people,
equipment and the environment against possible hazards, and to initiate stopping in an
emergency. Equipment, functional aspects and design guidelines for emergency stop are
listed in EN ISO 13850. The EN 60204-1 standard must also be observed.
The emergency stop command device with its two positive opening contacts is monitored by
the F-CPU. If the emergency stop is actuated, the F-CPU switches the downstream actuators
off via safe outputs in accordance with Stop Category 0 as per EN 60204-1. Before restarting
or acknowledging the emergency stop shutdown, a check is made as to whether the contacts
of the emergency stop command device have been closed and the feedback circuit of the
downstream actuators is closed.
To connect the two normally closed contacts of the emergency stop command device to the
AS-i bus, an AS-i interface module with two safe inputs (3SU1401-2EE60-6AA0) is installed in
the enclosures of the command devices.
Note
Emergency stop is not a way of reducing the risk. "Emergency stop" is a supplementary safety
function. (When "emergency stop" is operated, the motor must be shut down).
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Safety engineering with AS‑Interface in the SIMATIC ET 200SP, including typical circuit diagram
Function Manual, 08/2020, A5E44991382002A/RS-AB/002