This article is about the OT-One.

It's no-longer sold or actively supported by Opentrons, but we've kept this article here to help existing users. Please see our OT-2 Support articles for the most up to date information!


The OT-One S now features upgraded motors. This enables the user to run protocols in less than half the time of the previous OT-One. 

If you are upgrading the motors of your OT-One robot, please follow these steps, 


  • Y motors (2)

  • X motor (1)

  • Z motor (1)

  • Brass mount (1)

  • 4 Allen Keys - M5 M4 M2


  • Carefully unplug all motor cable wires before upgrading

Changing the Y motors

  1. Change the YL motor first. Use the provided allen key to loosen the 4 screws which mount the motor to the plate. Be careful to not strip the screws!

2. Loosen the 2 screws from the belt pulley.

3. Removing the screws will allow you to slide the belt pulley off of the motor rod.

 4. Slide the new motor rod into the belt pulley. In the upgrade kit we provided new belt pulleys but feel free to reuse the ones that were previously installed on your robot. 

The belt pulley should have the thinner wall facing outwards like so:

5. Mount the new motor to the plate. The cable connector should be facing toward the back of your robot. 

6. Make sure the belt is centered on the pulley before refastening the screws.

7. Repeat steps 2-6 for the YR motor!

Changing the A & B motors

  1. To change the A & B motors first loosen the screws on the black pipette stopper L brackets and slide them down to remove.

2. Remove the screw which fastens the acrylic actuator to the step motor thread.

3. Slide off the acrylic actuator.

4.Unplug the A & B motor cables.

5. Remove the 4 screws that fasten the motor to the acrylic.

6. Remove old motor

7. Fasten new motor to the acrylic with the 4 screws removed in the previous step.

8. Reassemble acrylic actuator

9. The flat side of the motor thread will need to be facing the acrylic actuator screw

10. Refasten acrylic actuator screw

11. Remount black pipette stopper L brackets

12. Repeat steps 1-11 for A motor

**The A motor cable connector will be facing towards the right unlike the B motor cable connector which is facing towards the front of the robot 

Changing the X motor

1. In order to change the X motor you will need to remove the entire A, B, Z gantry. 

2. Unscrew the camera mount if you have an OT-One Pro

If you have an OT One Hood or OT One Standard remove the  Locking screws 

3. Connect to your robot.
Click the "Select Port" drop down menu

4. The USB port your robot is connected to should appear. If not hit the refresh button

5. When it prompts you to "Home" choose "Cancel"

6. Drive the Z axis down until while holding the A & B gantry until it detaches and carefully place the A & B gantry on the deck of your robot

7. Disconnect Z home switch

8. You will need to detach the Z component to have access to the X motor screws. [Back of robot]

9. Below there will be similar screws to detach:

10. Loosen the motor screws which mount the X motor to the plate; remove the X motor with the belt pulley attached.

11. Insert the bottom motor screws in the plate before mounting new X motor 

12. Install new motor with belt pulley attached to motor rod and refasten the screws which mount it to the plate.

Changing the Z motor

1. Unscrew Z motor mount

2. Unscrew old motor 

3. Install new Z motor on plastic mount
4. Reinstall plastic mount

6. Change Z motor lead screw thread mount

7. Install new brass Z motor thread mount provided in upgrade kit

8. To remount the A & B gantry you will need to connect your robot to the app but do not Home.

9. Connect the new Z motor cable to the motor

10. Align the brass thread mount to the Z motor thread

11. Jog the Z axis up using your app

Upgrade your software

1. If you look in your motor controller box you will see an SD card
2. Remove the SD card

3. You will need an SD card reader to load the new software version
4. Click the button below to be redirected to Opentrons Github page

5. Click "Clone or Download" button

6. Download the Zip file to your desktop

7. Unzip the file
8. Locate the folder of the unzipped file

9. Select v2.0.0

10. Select the plus model of your robot
(in this tutorial we are upgrading an OT-One Pro to OT-One Pro Plus)

11. Copy the config and firmware files to SD card

12. Eject SD card
13. Insert SD card back into robot
14. Reconnect all motors cables to assigned motors
15. Check belt tensions by running a belt calibration
16.Reconnect Z home switch
17. Reconnect to your app once again selecting cancel when prompted to "Home"
18. Home each individual axis one at a time to troubleshoot any errors that might have occurred during assembly.

If you experience any issues please forward all question to ! :)

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