In a new electrical cabinet we have to apply to safety level PLd.
We have a circuit for direct online motors.
We will be using two power contactors in series to shut down power to the motors if an Estop is pushed.
We use S7 1500 failsafe plc. To comply with PLd, can we use only one safety digital output to drive both contactors? Or is for PLd one safe digital output for each contactor neccesarry? (this is not concering the maximum output power of the output, but conecering the safety level).
What about the readback of the contactors, can we bring the NC-contacts of the contactors in series on one safe digital intput or do we need one safe digital input for each contactor?
We have a circuit for direct online motors.
We will be using two power contactors in series to shut down power to the motors if an Estop is pushed.
We use S7 1500 failsafe plc. To comply with PLd, can we use only one safety digital output to drive both contactors? Or is for PLd one safe digital output for each contactor neccesarry? (this is not concering the maximum output power of the output, but conecering the safety level).
What about the readback of the contactors, can we bring the NC-contacts of the contactors in series on one safe digital intput or do we need one safe digital input for each contactor?