Thermo Scientific RO-20, Operating Manual

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4-2 RB-XXX-XXXXXX E RO-20
Löw 08.10.2008
Note The 12V alkaline cells should last several years. They run down exceedingly slowly. ▲
Observe the polarity indicators when installing the batteries.
Remove the AA cells if the instrument is to be inactive for a long period of time.
Caution Many instruments contain alkaline, carbon, lead, nickel cadmium or lithium
batteries. All batteries contain small amounts of heavy metals and other hazardous
materials and must be handled and disposed of properly. Lithium batteries present fire,
explosion and severe burn risk hazards. Do not expose the cell contents to water.
Recharge only batteries specifically designated as rechargeable and follow the
manufacturers recommendations on recharging. Do not puncture, mutilate or attempt to
disassemble, incinerate or heat above 100 °C (212 °F). Thermo Fisher Scientific
recommends that all batteries be recycled at appropriate licensed recycling centers or
disposed of as required by local ordinances and regulations.
▲
4.1.2 Desiccant
Replace the desiccant package when the crystals begin to turn clear or pink in color. Slip the
hose from the fitting on the old desiccant pack and onto the new one.
The used silica gel crystals can be repeatedly dried by heating them to 250 °F (120 °C) for 12
hours or to 400 °F (205 °C) for one hour.
Keep dried crystals in tightly sealed containers until ready for use. The snap-on cap of the
desiccant package has a small hole in it to allow the air to move through it. Make sure this
hole is not covered or clogged.
Note It is very important that the inside of the chamber assembly be kept dry to avoid
leakage currents due to moisture. If the desiccant becomes saturated and the unit becomes
erratic due to moisture, renew the crystals and cycle the instrument between room temperature
(or lower) and +140°F, three or four times to flush the chamber air across the desiccant.
▲
4.1.3 Calibration
For maximum accuracy, the RO-20 should be calibrated at approximately the same air
pressure as is expected for its use. If the conditions for calibration and for use are necessarily
different, an offset may be used during calibration so that the instrument will read properly
when put to use.
Table 2-1 or Table 2-2 can be used to select the proper offsets in this case.
Interpolate where appropriate.