SERVOSTAR™ 300

Technical description 07/2010 Kollmorgen
6.8.2 Emergency Stop: Standards
The emergency Stop function is used for the fastest possible shut-down of the machine
in a dangerous situation. The Emergency Stop function can be triggered by the actions of
a single person. It must be fully functional and available at all times. The user must not
have to work out how to operate this mechanism.
The Emergency Stop function is defined by IEC 60204.
In addition to the requirements for Stop, the emergency Stop must fulfil the following
requirements:
� emergency stop must have priority over all other functions and controls in all operating
situations;
� 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 (e.g. by
using mechanical latching devices that do not require an external supply of energy,
by counter-current braking in Stop Category 1);
� the reset must not initiate a restart.
If necessary, provision must be made for the additional connection of emergency stop
devices (see IEC 60204, "Requirements for emergency stop devices"). The Emergency
Stop must be effective as a stop of either Category 0 or Category 1.
The Emergency Stop Category must be determined by a risk evaluation of the machine.
Category 0
Only hard-wired, electromechanical components may be used for the Category 0 Emergency
Stop function. It must not be triggered using switching logic (hardware or software),
by transferring commands via a communication network, or via a data link.
The drive must be shut down using an electromechanical circuit. If the connected servo
motor has an integrated brake, this must always be controlled by an electromechanical
circuit as well.
Category 1
With the Category 1 Emergency Stop function, there must be absolute certainty in terms
of the power supply for the machine drives being switched off (i.e., secured) using electromechanical
components. Additional Emergency Stop equipment may be connected.
Bringing the motor to a standstill by interrupting the mains supply and using controlled
electronic braking. The 24 V supply for the servo amplifier must remain constant. The
issue of which circuit should be used is highly dependent on the requirements of the
application at hand.
In most servo motors a brake has only the function of a holding brake. To ensure an
emergency stop function, the braking torque that is required must be checked. If the holding
brake fulfills the dynamic requirements, it must be taken into acount that this application
will cause increased wear.
Examples for implementation can be found in the Product WIKI on page "Stop and
Emergency Stop Function".
34 SERVOSTAR 300 Instructions Manual