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                  1. Support
                  2. Basic calibration
                  3. Door sensor calibration (CORE One, CORE One L)
                   

                  Contents

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                  Door sensor calibration

                  (CORE One, CORE One L)

                  Relevant for

                  CORE One family
                  CORE One+
                  13 comments
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                  The Prusa CORE One/+ and Prusa CORE One L are enclosed printers with a door. It is necessary for the door to be closed for printing. 

                  The closed door improves the print quality, but also ensures your safety, concerning possible injuries from the moving components. 

                  Procedure

                  To calibrate the door sensor position, navigate to LCD Menu -> Control -> Calibrations & Tests -> Door sensor calibration. An introductory message is shown on the screen, select Calibrate. 

                  The printer prompts to first close the door. Once the door is closed, press Continue. 

                  Then, the printer prompts to open the door, and gradually tighten the sensor tension screw. Tighten the tension bolt by half-turn for each iteration. After each adjustment, observe the door sensor switch emerging from the front profile hole. 

                  Once tightened, press Continue. Follow the in-screen instructions, the printer can instruct to further tighten the tension screw, to loosen it, or to continue to a successive step. 

                  When the printer prompts you, place your hand as shown in the screen picture below. 

                  Only place the hand inside the door when the printer prompts you to do so! 

                  Once the sensor is calibrated, you should hear an audible click from the door sensor area when regularly opening and closing the door. 

                  After the calibration, the status can be checked in LCD Menu -> Info -> Sensor Info -> Door Sensor. 

                  Safety feature

                  By default, the printer has a safety feature that pauses printing if the door is open during a print. 

                  In-screen message shown when a door is open during a print.

                  This feature can be accessed and toggled on or off by navigating in LCD Menu -> Settings -> Hardware -> Door sensor. 

                  The safety feature is there to prevent user injury. If deactivated, please be aware that you might risk injury from the moving printer's parts. 
                  If you are experiencing issues with the door sensor, such as an unsuccessful calibration, and the steps in this article are not working, please do not hesitate to reach out to our technical support. 
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                  Topics

                  • Calibration
                    • Basic calibration
                      • Idler screw tension
                      • Gearbox alignment (CORE One L, CORE One, XL, MK4/S, MK3.9/S)
                      • Door sensor calibration (CORE One, CORE One L)
                      • Live adjust Z
                    • Advanced calibration
                    • Calibration Error Messages

                  6 comments

                  Log in  to post a comment
                  Macmagoo
                  •
                  Followed JRBloom instructions and it calibrated at the first attempt.
                  Reply
                  bruhnstv
                  •
                  Still, I will leave it disabled - unless you tell me that opening the door no longer resets the printer! Really, there should an option to execute an immediate graceful pause if the door is opened during a print.
                  Reply
                  jWintour
                  •
                  Remember when they said, "don't tighten the door sensor switch too much, it needs to be loose"? If it's not loose enough, then backing off the tension switch doesn't let the switch move back - it sticks, and the firmware thinks the door is always closed. Rather than take it all apart to loosen the switch mount just, after you loosen the tension screw, just reach in and push the switch back against the screw tip again.

                  Personally, I think the tension screw is too short. In my case I couldn't make it push the switch forward enough.
                  Reply
                  Maximus
                  •
                  Per instructions, tightened 1/2 turns until door would not shut. Backed all the way out and can hear audible click but still not calibrated.
                  Reply
                  hakkaisha
                  •
                  Seemd to be something wrong with the test for me still got error to continue tightening after tightening the screw to the maximum, so skipped it since i could he the switch when closing the door. Seems to work as intended any way since it warns me about the dor being open.
                  Reply