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electroPioreactor
Video on YouTube — shot 2026-09-22 by andeye (Laura Currie, edit; Martin Currie and Bingqiao Zhao on camera). Loads from YouTube only when you press play.

Vial holder and XR optics

Carry on with Pioreactor’s 40 ml v1.5 hardware setup guide, with these changes. The A small jumper on the HAT. In the position closest to the LED outputs it feeds the 12V supply to PWM channels 1 to 4. must already pass its check in Raspberry Pi and HAT: item 4 here covers it.

  1. Do not fit the v1.5 optics. Keep those parts for the Pioreactor's extended-range optics. Extra eye-spys read light scattered at 45° and 135° as well as 90°, for a lower OD detection limit..

    Why, and which of those parts the XR kit reuses

    AEP0.2 is XR from the start; the XR upgrade would only have you strip the v1.5 optics back out. From the v1.5 kit, the XR assembly reuses 2 A small Pioreactor sensor board that reads light from the vial. The eye-spys are chained together with STEMMA-QT wires., 3 optics covers, 12x 8 mm screws, 1 LED cap and the 50 mm A small 4-pin plug-and-socket standard for sensor boards. The eye-spys and the temperature sensor daisy-chain over it. wire. The XR kit supplies the other eye-spys, its own top vial holder and the O-ring. Upgrading a Pioreactor that is already built? Follow the XR disassembly guide to recover those parts.

  2. Follow the wetware assembly, with these changes: set the vial’s own cap aside and skip the stainless steel ports. Fit the X-section o-ring into the XR top vial holder and the round o-ring into the bottom vial holder.

  3. Fit the XR upgrade kit. Fix each eye-spy under an optics cover with four 8 mm screws: the one labelled 0x4B at 45°, the white-marked one at The reference photodiode position on the vial holder (photodiode channel 1=REF in config.ini). Its eye-spy is the white-marked one., the unmarked one at 90°, the last at 135°. Fit the heater PCB, thermal pad, LED and LED cap, then connect the STEMMA-QT chain, yellow wire down.

  4. Attach the wetware to the HAT assembly. Drive four screws into the square nuts until flush, and no further. Fit the 10 mm screw under the button extension and the four 8 mm corner screws, push the flat flex cable into the orange connector, and plug the stirrer into One of the HAT's five switched power outputs. In this build: 1 stirring, 2 media pump, 3 waste (product) pump, 4 CO₂ solenoid (relay), 5 heating. 1.

  5. Connect the 12V supply to the The Pioreactor circuit board that plugs onto the Raspberry Pi's pin header. It carries the PWM and LED outputs and the 12V barrel jack.’s barrel jack (external power).

Only with temperature kit

If you have the An optional Pioreactor kit. Its MLX90632 far-infrared sensor reads the vial's temperature without contact, replacing the thermistor., fit it. Lift the cover off the A sensor position on the vial holder, covered when not in use. In this build the Precision Temperature Upgrade Kit's sensor seats there., run the STEMMA-QT wire from the sensor PCB to the nearest eye-spy, and seat the sensor in SPEC, LED pad to the right.

Notes
  • XR adds 45° and 135° scattering to 90°, for a lower Optical density: how cloudy the culture is, read from scattered light. It tracks cell growth. detection limit and earlier signs of growth.
  • If a square-nut screw meets resistance, back it out and check its tip for plastic debris before driving it home.
  • The Precision Temperature kit’s MLX90632 far-infrared sensor replaces the thermistor for faster, hotter, contactless temperature control. Its optional screws may not fit past the STEMMA-QT cable.
  • Four or more Pioreactors on one bench can share one multi-port charger instead of one supply each: see powering a cluster.

Parts

  • 1×Pioreactor 40 ml v1.5earlier step
  • 1×Pioreactor 40 ml glass vialpart
  • 1×Magnetic stir barpart
  • 2×Eye-spypart
  • 3×Optics coverpart
  • 12×8 mm screwpart
  • 1×LED cappart
  • 1×50 mm STEMMA-QT wirepart
  • 1×XR upgrade kitpart
  • 1×XR top vial holderpart
  • 1×XR O-ringpart
  • 1×Precision Temperature Upgrade KitpartOnly with temperature kit
  • 1×12 V power supplypart

Tools

  • 1×Phillips PH0 screwdrivertool

Check your work

  1. How many A small Pioreactor sensor board that reads light from the vial. The eye-spys are chained together with STEMMA-QT wires. are fitted around the vial holder?

    Show the answer

    Answer: Four

    • If you see Two: Those are the v1.5 optics. Recover the parts the XR assembly reuses with the XR disassembly guide (linked under Do not fit the v1.5 optics), then fit the Pioreactor's extended-range optics. Extra eye-spys read light scattered at 45° and 135° as well as 90°, for a lower OD detection limit..
    • If you see Three: One is missing. The XR kit has four positions: 45°, The reference photodiode position on the vial holder (photodiode channel 1=REF in config.ini). Its eye-spy is the white-marked one., 90° and 135°.

  2. Which position holds the A small Pioreactor sensor board that reads light from the vial. The eye-spys are chained together with STEMMA-QT wires. labelled 0x4B?

    Show the answer

    Answer: 45°

    • If you see REF: Swap them round: 0x4B at 45°, the white-marked one at The reference photodiode position on the vial holder (photodiode channel 1=REF in config.ini). Its eye-spy is the white-marked one., the unmarked one at 90°, the last at 135°.
    • If you see 90°: Swap them round: 0x4B at 45°, the white-marked one at REF, the unmarked one at 90°, the last at 135°.
    • If you see 135°: Swap them round: 0x4B at 45°, the white-marked one at REF, the unmarked one at 90°, the last at 135°.

  3. How is the An optional Pioreactor kit. Its MLX90632 far-infrared sensor reads the vial's temperature without contact, replacing the thermistor.'s sensor fitted?

    Only with temperature kit

    Show the answer

    Answer: In SPEC, LED pad to the right, wired to the nearest eye-spy

    • If you see In SPEC, LED pad to the left, wired to the nearest eye-spy: Turn it round so the LED pad is to the right.
    • If you see In SPEC, LED pad to the right, with no STEMMA-QT wire: Run the A small 4-pin plug-and-socket standard for sensor boards. The eye-spys and the temperature sensor daisy-chain over it. wire from the sensor PCB to the nearest A small Pioreactor sensor board that reads light from the vial. The eye-spys are chained together with STEMMA-QT wires..

  4. What is plugged into the The Pioreactor circuit board that plugs onto the Raspberry Pi's pin header. It carries the PWM and LED outputs and the 12V barrel jack.'s barrel jack?

    Show the answer

    Answer: The 12V supply

    • If you see Nothing yet: Plug in the 12V supply. The An electric valve on PWM channel 4 that opens to sparge. It must be 3-way venting (3/2), so the line vents when it closes. needs more power than the Pi supplies; without it, Bubbling gas through the culture. Here, CO₂ from the cylinder flows down the anode on a timer set in the electroPioreactor job. fails and looks like a gas train fault.
≈ 0.03 g CO₂e per view