Malvern Instruments Spraytec, User Manual

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Vertical mounting – short bench and long bench options are available as for
the angled model. A Bench shroud is provided with these to stop spray be-
ing deflected back into the measurement zone; this is described below.
Spacing the modules on the X-bar
Guidelines:
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For nasal sprays start at the minimum distance (150mm from the Receiver).
Unless the spray fouls the detector (shown by the background measure-
ment falling), there is no need to increase the distance from the Receiver.
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For any spray, if the distance from the Receiver is too great, “vignetting”
may occur. This is caused by a lack of data reaching the top end detectors. It
can cause narrow mode results; see Chapter 6.
Adjusting the feet
The laboratory Spraytec X-bar must be kept at an angle of 12°. The instrument
will be installed like this, but if the feet are ever moved vertically out of position
readjust them as described in Appendix E.
,
Transmitter
The Transmitter contains the laser source. This produces a collimated beam of
10mm diameter with a wavelength of 632.8nm.
The laser beam from the Transmitter passes through the measurement zone
where spray is sprayed, then through a lens and protective windows to the
detector array in the Receiver. The laser beam is directed through the spray and
the resultant scattered light is detected by the detectors in the Receiver.
'
N o t e
. The Spraytec instrument is a Class 3R laser product.
Both the Transmitter and Receiver are installed inside cast aluminium covers.
The cover body and end caps are painted with solvent protective paint. A rubber
seal between the cover body and the end cap stops the ingress of moisture, dirt or
contamination. This gives an IP65 protection rating in normal use. The power
switch is on the front of the Transmitter.
C H A P T E R 3
S p r a y t e c
P a g e 3 . 4
M A N 0 3 6 8