Bacharach 50 manual Maintenance, Battery Installation, Sensor Replacement

5.Allow span gas to flow until the displayed reading stabilizes – approx. 3 minutes. Then, using Calibra- tion Tool 06-9453 (supplied in Calibration Tool / Cup Kit 19-3242), turn the Span Adjust potentiom- eter until the displayed reading matches the concentration stamped on the Span Gas Cylinder.

6.Calibration is now complete. Turn off the Regulator and remove the calibration equipment.

Maintenance

Battery Installation

Remove the slotted screw from the rear of instrument; then lift off the front case.

Install a 9V Alkaline battery (Duracell MN1604 or equiv.) in the location shown in Figure 3; then reinstall the front case.

Sensor Replacement

Figure 3. Battery

Location

The sensor needs replaced when it can no longer be calibrated to the Span Gas Cylinder value using the Span Adjust potentiometer.

1.See Figure 4. Remove the screw from the rear of the instrument; then lift off the front case and remove the printed circuit board assembly.

2.Unplug the old sensor and dispose of it properly.

3.Inspect the sensor gasket and filter. Replace an item if is torn, deformed, or contaminated with dirt.

4.Remove the wire-jumper from the pins of the new sensor; plug in the sensor; then reassemble the instrument.

5.Calibrate the new sensor.

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