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Stop and Emergency Stop Function

Valid for AKD, S300, S400, S600, S700

The control functions Stop, Emergency Stop and Emergency Off are defined by IEC 60204. Notes for safety aspects of these functions can be found in ISO 13849 and IEC 62061.

Stop

The Stop function is used to shut down the machine in normal operation. The Stop functions are defined by IEC 60204.

The Stop Category must be determined by a risk evaluation of the machine.

  • Stop function must have priority over assigned start functions.
  • Category 0 and Category 1 Stops must be operable independently of the operating mode, whereby a Category 0 Stop must have priority.
  • If necessary, provision must be made for the connection of protective devices and lock-outs.
  • If applicable, the Stop function must signal its status to the control logic.
  • A reset of the Stop function must not create a hazardous situation.

The following stop categories are defined:

Stop Category 0

Shut-down by immediate switching-off of the energy supply to the drive machinery (i.e. an uncontrolled shut-down). .
With the safety function STO the drive can be stopped safely using its internal electronics.
Also possible is the use of a contactor control, for example: Wiring example Emergency Stop with Stop Category 0

Stop Category 1

A controlled shut-down, whereby the energy supply to the drive machinery is maintained to perform the shut-down, and the energy supply is only interrupted when the shut-down has been completed.
Wiring example Emergency Stop with Stop Category 1, contactor control

Stop Category 2

A controlled shut-down, whereby the energy supply to the drive machinery is maintained.
Wiring example with Stop Category 2, contactor control

Emergency Stop

The Emergency Stop function is used for the fastest possible shutdown of the machine in a dangerous situation. The Emergency Stop function is defined by IEC 60204. Principles of emergency stop devices and functional aspects are defined in ISO 13850.The Emergency Stop function will be triggered by the manual actions of a single person. It must be fully functional and available at all times. The user must understand instantly how to operate this mechanism (without consulting references or instructions).

The Stop Category for the Emergency Stop must be determined by a risk evaluation of the machine.

In addition to the requirements for Stop, the Emergency Stop must fulfill the following requirements:

  • Emergency Stop must have priority over all other functions and controls in all operating modes.
  • The energy supply to any drive machinery that could cause dangerous situations must be switched off as fast as possible, without causing any further hazards ( Stop Category 0, e.g. with STO) or must be controlled in such a way, that any movement that causes danger, is stopped as fast as possible (Stop Category 1).
  • The reset must not initiate a restart.

Wiring example Emergency Stop with Stop Category 0, contactor control
Wiring example Emergency Stop with Stop Category 1, contactor control

Emergency Off

The Emergency Off function is used to switch-off the electrical power supply of the machine. This is done to prevent users from any risk from electrical energy (for example electrical impact). Functional aspects for Emergency Off are defined in IEC 60364-5-53.The Emergency Off function will be triggered by the manual actions of a single person.

The result of a risk evaluation of the machine determines the necessity for an Emergency Off function.

Emergency Off is done by switching off the supply energy by electro-mechanical switching devices. This results in a category 0 stop. If this stop category is not possible in the application, then the Emergency Off function must be replaced by other measures (for example by protection against direct touching).