
OZONE ANALYZER BMT 964 Manual, Rev. 04/2021
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Appendix B: Bench Top Version BMT 964 BT
General Description
The OZONE ANALYZER BMT 964 BT is the portable version of the standard BMT 964. The
instrument is not much bigger than the standard BMT 964. For safety reasons it is powered via a
wall mount power supply 24 VDC with wide range power input.
The BT model has a throttle valve and flow meter attached on the right side, and a Catalyzing
Cartridge (catalytic ozone destruct) on the left (sample gas outlet).
The sample gas enters the throttle valve through a fitting for 3 x 5 mm (1/8" x 3/16") PTFE
tubing, and then via the flow meter enters the BMT 964 through a sample gas filter with a re-
placeable white filter insert. Upon exiting the analyzer, the sample gas passes through the Catalyz-
ing Cartridge where the ozone is destroyed.
Operation
The operation of the BMT 964 BT is the same as of the standard BMT 964. Care must be taken
using the Catalyzing Cartridge, which may never see water or humidity. This might damage the
catalyzing material. The sample gas filter can only keep dirt from entering the analyser, not hu-
midity.
As an option the OZONE ANALYZER BMT 964 BT may be ordered equipped with the Inter-
nal Purge Unit, which consists of a built-in 3-way solenoid valve plus air pump with particle filter,
for fully automatic purging and zeroing the instrument.
This option makes sure, that the cuvette is flushed with ambient filtered air (zero gas) upon acti-
vating zeroing, as described on page 23. The pressure head at the outlet of the Catalyzing Car-
tridge must not exceed 100 mbar to the ambient. Otherwise the built-in air pump will not bring
the ozone out of the cuvette and false zero readings will be the result.