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electroPioreactor

Admit CO₂

The valve train was built and left to fixture in CO₂ gas train.

  1. Work in a well-ventilated room. Put the SodaStream cylinder into its holder at the rear of the raft.
  2. Put on all PPE, including cryogenic gloves.
  3. Screw the Drops the cylinder's pressure (about 60 bar when full) to a working pressure, about 1 bar here. Its flathead screw fully anti-clockwise is closed. onto the right-angle cylinder adapter.
  4. Back off the adapter’s pin screw, seat the adapter’s washer, screw the adapter onto the cylinder in one swift, decisive move, and tighten it with the gas cylinder wrench, regulator to the front and 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. to its right.
  5. Open the cylinder: screw the adapter’s pin screw fully down. If the adapter leaks, tighten it further.
  6. Read the two gauges. The left shows the cylinder pressure, your warning that it is running out; the right shows the pressure reaching the solenoid. The The MEP's budget CO₂ regulator. Its outlet pressure is fixed, so the needle valve alone sets the CO₂ flow. Left gauge: cylinder pressure; right gauge: pressure reaching the solenoid.’s outlet pressure is fixed, so there is nothing to set.
  7. Check for leaks: with the A fine-adjustment valve on the solenoid's front port. It sets how fast CO₂ flows; turn clockwise to close. closed, turn the The dial on the front of the solenoid. 0 is normal (closed without power); 1 holds the valve open. to 1 and watch the right-hand gauge for 60 seconds. Any drop means a leak upstream of the needle valve. Turn the override back to 0.
  8. Remove the compression nut and The ring inside a compression fitting. Tightening the nut squeezes it onto the tube to make a gas-tight seal. from the top of the needle valve, thread the nut onto the 4 mm polyurethane CO₂ tube, and push the tube fully onto the needle valve (dip it in hot water if it will not go). Refit the ferrule, and screw the nut down.
  9. Cut the tube just long enough to run over the regulator and down to the vial cap’s CO₂ inlet (cut every other unit’s tube to the same length), and push a 1/8” hose barb to A standard medical screw fitting. A male luer (the spigot) screws into a female luer (the socket). In this build, male ends mark outlets. lock adapter into the free end (hot water if needed).
  10. Connect the tube’s luer to the vial cap’s CO₂ inlet luer.
  11. Route the solenoid lead down behind the Pioreactor and through the pumps, and plug it 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. 4.
Notes
  • With a fixed-pressure regulator the needle valve is the only flow control. It is set in Calibrate CO₂ flow.
  • Carrying the unit elsewhere: keep the regulator, solenoid and needle valve assembled, and take the cylinder off.

Parts

  • 1×FZone CO₂ regulatorearlier step
  • 1×Solenoid valveearlier step
  • 1×Right-angle cylinder adapterpart
  • 1×SodaStream CO₂ cylinder (blue screw-in)consumable
  • 1×Polyurethane CO₂ tube, 1 mpart
  • 1×1/8" barb to male luer lockpart
  • 1×O-ring vial capearlier step

Tools

  • 1×28 mm gas cylinder wrenchtool
  • 1×Cryogenic glovestool
  • 1×Eye/face protectiontool

Check your work

  1. A fine-adjustment valve on the solenoid's front port. It sets how fast CO₂ flows; turn clockwise to close. closed and override at 1, what does the Drops the cylinder's pressure (about 60 bar when full) to a working pressure, about 1 bar here. Its flathead screw fully anti-clockwise is closed.'s right-hand gauge do over 60 seconds?

    Show the answer

    Answer: Holds steady at the same reading

    • If you see Falls steadily from its first reading: A joint upstream of the needle valve leaks. Pipette washing-up liquid in water onto each An anaerobic thread sealant: it cures only without air, inside a tightened thread. Fixtures in 10 to 60 minutes at 22 °C; full pressure after 24 hours. joint and watch for bubbles.
    • If you see Stays at zero from the start: The cylinder is not open: screw the adapter's pin screw fully down.

  2. Which 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. is 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. lead plugged into?

    Show the answer

    Answer: PWM 4

    • If you see PWM 3: Move it to PWM 4: the electroPioreactor job drives the relay there. PWM 3 is the media pump's.
    • If you see PWM 2: Move it to PWM 4: the electroPioreactor job drives the relay there. PWM 2 is the waste pump's.
≈ 0.02 g CO₂e per view