OZONE MONITOR BMT 932 Manual, Rev. 02/2021
13
10
Pneumatic Installation
The OZONE MONITOR BMT 932 has either 1, or 3, or 6, sample gas inlet fittings (according
to the model ordered). The fittings are bulkhead compression fittings for ¼'' OD (.250" x .156"),
or 6 mm OD (6 x 4 mm) tubing. The cabinet version BMT 932C accepts only 1/4" tubing (refer
to Appendix C, page 48). Tubing material has to be fluorinated plastic, preferably transparent
FEP to make any internal droplets or coarse dirt visible. Sample tubing length should be as short
as possible. Maximum recommended length is 20
m.
The instrument intentionally has no internal dust filter. The
reason is that the dust filter has to protect not only the ozone
monitor, but also has to protect the inner surface of the
sample gas tubing leading to the monitor. Thus the filter has
to be mounted at the inlet of the sample tubing. The
OZONE MONITOR BMT 932 comes with one fitting
(932-MALEFIT) per channel. This fitting provides fast con-
nection between the sample tubing inlet and the filter holder
(932-HOLDER). This fast connection simplifies replacement of the filter inserts on a regular
basis.
Caution:
We strongly recommend not to use SS tubing. Use of SS tubing will most likely lead to
measurement errors. Since in most installations of other ozone monitors there are no sample gas
filters provided at the sample tubing inlets, this older tubing probably is
more or less dirty inside resulting in more or less ozone destruction in the
sample gas. This is the reason why we strongly recommend that old tub-
ing be removed and replaced, preferably by transparent FEP tubing. We
strongly recommend to replace SS tubing by FEP tubing in older installa-
tions.
One outlet fitting is provided for the sample gas after being measured.
The outlet fitting is also for ¼'' or 6 mm tubing. Inside the OZONE
MONITOR BMT 932 an ozone catalyst is installed to remove ozone from the sample gas re-
leased from the outlet fitting. From this catalyst particles might come which then are contained in
the out gas. In very clean environments the sample gas outlet should be vented to an exhaust.
10.1
Sample Gas Filters
It is very important that the sample gas tubes and
the ozone monitor are kept clean inside. The
OZONE MONITOR BMT 932 must always be
operated with one clean sample gas filter
(932-HOLDER) at the inlet of each sample gas
line. One filter holder per channel, one fitting for
mounting the filter holder, and 200 filter inserts
are shipped with the instrument. The filter inserts are of fine pure glass fiber to remove nearly
special mounting of filter in the sample gas line near the
inlet of the tubing (order code: 932-ADAPT. Special
inline filter on request, not included.
Please note: do not use the 932-HOLDER, it is not de-
signed for inline configurations!)
932-HOLDER & 932-MALEFIT:
standard mounting of filter at the inlet of the
sample gas tubing (included with every
BMT 932)
1
3
2
932-HOLDER
