Qubic System QS-220-PL, User Manual

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QS-220-PL
6.3.2
ADDING POWER-CUT CIRCUIT WITH E-STOP BUTTON
If specific SIL/PL rated level needs to be achieved, it might be necessary to install a
power cut-off device. Two contactors connected in series and controlled by safety relay
can be used to provide or cut-off power line to QS-SB2 power cabinets. When safety
function on safety relay input is triggered, a safety relay will switch off the contactors,
thus cutting-off the power to the platform. To apply this solution, ML UP connection
cables needs to be replaced with prepared jumper as described in section 6.3.1
INFO
To achieve required safety performance level it is necessary to perform safety
risk assessment at customers site.
Example application of power line contactors and E-STOP button:
INFO
In order to increase SIL/PL level it’s a good practice to apply well-known con-
tactors of two different manufacturers in order to decrease probability of failure
resulting from serial production.
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