3-6 | Model 120HD Hydrogen Analyzer
Maintenance
Battery
The 120HD analyzer uses (1) 6V No. 521 Energizer Industrial Alkaline
Lantern Battery. When the low battery warning indicator lights up and
the battery runs down to the extent that it is impossible to adjust the
digital display to 120.0 ±0.1, replace the battery following the procedure
described in Chapter 1.
repairs
Check the calibration following any repairs. Recalibration requires a
known mixture of hydrogen and air or nitrogen. Hydrogen gas is flam-
mable, and in a mixture with air concentrations over 4% - 5%, it is explo-
sive. For this reason, mixtures of 20% hydrogen in air generally can’t be
obtained from commercial sources.
Do not attempt to make such a mixture and recalibrate the analyzer
unless proper equipment, personnel, and expertise is available. Send
the analyzer back to the AMETEK factory for recalibration.
Uncontaminated failed units or electrical subassemblies should be
returned to AMETEK for failure evaluation by securing an RMA fol-
lowing the procedure in Chapter 1 under “Technical Support.”
NOTE