Eppendorf Galaxy CO2 Sensor - Manual (Page 72)

Equipment options
Galaxy
® 170 R/170 S CO
2
Incubators
English (EN)
72
Detailed removal and installation instructions are provided (see Removing and replacing O
2
sensor on p. 76).
12.4 O
2
control (1 - 19 %) (Galaxy R only)
This oxygen control option is designed to cover the 1 - 19 % range by adding nitrogen to bring the level
below ambient. If you have the 0.1 - 19 % oxygen control option, (see
O
2
control (0.1 - 19 %) (Galaxy R
only) on p. 80); or if you have the 1 - 95 % oxygen control option, (see O
2
control (1 - 95 %) (Galaxy R only)
on p. 83).
12.4.1 Setting up the N
2
tank
Prerequisites
Before you set up your oxygen control, ensure that you have the proper equipment for your nitrogen
supply:
• 2 cylinders of nitrogen, regulation size W
• 1 two-stage pressure regulator
• 1 Inline pressure regulator
• 6 mm PVC tubing
• tubing clips
Set up the nitrogen tanks as follows:
1. Inspect them to ensure there are no leaks or other damage.
2. Check that the two-stage pressure regulator valve and the inline pressure regulator valve are closed by
trying to turn their knobs in a counter-clockwise direction; the knobs should be at the stop point.
3. Place the inline pressure regulator close to the incubator.
4. Securely attach the two-stage pressure regulator to the nitrogen tank’s outlet and to the inline pressure
regulator’s inlet with tubing, securing both ends with clips.
5. Connect the inline pressure regulator’s outlet to the incubator’s N
2
inlet on the right side of the control
box at the rear of the incubator (see Fig. 2-3 on p. 11); secure both ends with clips.
6. Proceed as indicated in (see Setting up oxygen control on p. 72).
12.4.2 Setting up oxygen control
1. Remove the black plastic protective cover from the hydrophobic filter cap (making sure that the
hydrophobic filter cap is not removed with it), located in the rear wall of the incubator chamber. Retain
the cover for use when you clean the chamber.
2. Open the nitrogen gas supply from the tank. Set the N
2
tank’s outlet pressure gauge to 1.5 bar.
3. Set the nitrogen regulator to 14.5 PSI (1 bar). The nitrogen will be fed into the incubator through a filter
that is already installed in the gas line. The gas flow rate is approximately 20 liters/minute.
To add an automatic gas cylinder changeover instrument: with the incubator turned off,
connect its inlet to the two-stage pressure regulator’s outlet, and the changeover instrument’s
outlet to the inline pressure regulator’s inlet with tubing, securing the ends with tubing clips.