Barnstead Thermolyne Corporation 494 Series, Operation Manual And Parts List

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11
Maintenance of the Bantam Holder 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.
Calibration
Calibrate the Direct Reading Meter as follows:
1. Set the on/off switch to the “off” posi-
tion.
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 resis-
tance.
Maintenance and Servicing
Warning
To avoid electrical shock, always
disconnect the power supply
before maintenance and
servicing. Refer servicing to
qualified personnel.