The optional C990-G0xx push-button extensions for the Control Panels CP2xxx and CP39xx from Beckhoff Automation provide additional input options. Push-button extensions that match the design of the Control Panels enable application-specific use of electromechanical buttons. Selection and key switches can also be integrated. The push-button extension is located below the touchscreen. The number of buttons that can be added depends on the display size. The actuation of the emergency stop and other buttons is transferred to the controller via USB and can be read with TwinCAT. Optionally, customers may use the signals for additional purposes. The emergency stop has two N/C contacts and one N/O contact. The signal of the N/O contact is transferred to the controller. The two N/C contacts can be used by the customer. One button actuates two N/O contacts, one of which is available as a potential-free contact for use by the customer. The indicator lamps are controlled via USB. 

The optional C990-G0xx push-button extensions for the Control Panels CP2xxx and CP39xx from Beckhoff Automation provide additional input options. Push-button extensions that match the design of the Control Panels enable application-specific use of electromechanical buttons. Selection and key switches can also be integrated. The push-button extension is located below the touchscreen. The number of buttons that can be added depends on the display size. The actuation of the emergency stop and other buttons is transferred to the controller via USB and can be read with TwinCAT. Optionally, customers may use the signals for additional purposes. The emergency stop has two N/C contacts and one N/O contact. The signal of the N/O contact is transferred to the controller. The two N/C contacts can be used by the customer. One button actuates two N/O contacts, one of which is available as a potential-free contact for use by the customer. The indicator lamps are controlled via USB.