Marconi TF 933C User Manual

compression
cell
electrode
using
the
lead
provided.
Ensure
that
will'
the
larger
plugs
goes
to the
main
instrument
and
do
not
attempt
to
into
smaller
sockets
on the
compression
cell.
Thore
is no
significance
in
of the
individual
leads
as
there
is
no
polarity
to observe
and
the
connect
ionn
be
reversed
without
effect.
The
GREEN
socket
ig not
required
for
the
cell
supplied with
this
instrument
and
the
other two
sockets labelled
CA
CHECK
are
provided
for test
purposes
as
described
in
Chapter
Calculator
scales
If a
seale is
available for the
substance to be tested slide the scale into
position
-
see Fig.
1.1. If there
is no scale
available
then select the
appropriate
calibration
data sheet.
The following
sections give the general method of operating
the
instrument.
Detailed procedures that apply to particular materials
are given in
the
calibration
data
supplied
for each group of substances.
2.3
PREPARATION
OF
SAMPLE
Granular or
powdery
substances
The
instrument
may be
used
in two
ways:
(a)
whole
grain
(b)
the
flour
or
meal
produced
by
coarse
grinding
Tests
on
unground
granular
substances
are
strongly
influenced
by the
surface
moisåare.
Tests
on
whole
grains
of
wheat
indicate
substantially
the
bran
moisture.
For
this
reason
it is
advisable
to
test
the
sample
both
whole
and
ground,
to
give
an
indication
of
the
moisture
distribution
as
well
as
its
average
value.
The
fineness
of
grinding
is
not
important
but
the
loss
of
moisture
which
may
occur,
especially
with
damp
samples,
must
be
minimized.
Therefore
avoid
very
fine
grinding.
After
grinding,
flush
out the
grinder
with
the
sample
to be
tested
and
discard
the
first
ground
sample.
Fibrous
material
In
general
the
procedure
is
the
same
as
for
granular
materials.
The
cavity
for
the
test
cell
should
be
approximately
half
filled
with the
specimen
tmtilpacked
tmiformly,
pressing
the
specimen
down
in
much
the
same
manner
as
filling
a
pipe.
After
the
test
the
compressed
plug
should
be
about
1.6
mm
thick,
or
3.2
mm
for
the
large
cell.
2.4
LOADING
THE
COMPRESSION
CELL
The
following
description
may
appear
complicated
because
each
detail
is
mentioned
but
the
procedure
will
be
found
quite
simple
and
convenient.
933C
(1b)

Marconi TF 933C Specifications

General

Brand	Marconi
Model	TF 933C
Category	Measuring Instruments
Language	English