Maintenance And Servicing; Calibration - Thermo Scientific 494 Series Operating Manual

Calibration

Thermo Scientific

Maintenance and Servicing

Section 6
Maintenance of the Bantam Deionizer should be minimal, involving
cartridge replacement and o-ring seal replacement. Also, an occasional
calibration check of the purity meter might be necessary. Cartridges should
be stored away from heat.
Warning To avoid electrical shock, always disconnect the power supply
before maintenance and servicing. Refer servicing to qualified personnel.
Calibrate the Direct Reading Meter as follows:
1. Set the on/off switch to the "off " position.
2. Check the zero alignment of the meter needle to the meter scale. If
required, rotate the zero adjustment screw until the meter needle is
aligned with the line indicating the beginning of the meter scale. The
zero adjustment screw is located on the face of the meter below the
scales.
3. To calibrate the meter further, connect a known resistance across the
cell terminals. A 50,000 ohm resistance should correspond to "0.05"
on the meter scale.
4. With the on/off switch set to "on," adjust the potentiometer
(screwdriver adjustment) at the bottom of the meter case to make the
scale reading correspond to the simulated resistance.
s
Deionizer 6-1