Table of Contents
Advertisement
EIALKERG
.
.
.
5.1.3
Electrometer
offset adjustments
e)
Turn the emission
on.
Adjust
the
electrometer
offset
as
follows:
f)
Repeat steps
d)
and
e)
until the «Emission
error» error
message appears,
a)
Pull the coaxial plug
on
the electrometer preamplitier
and
shield the BNC connector with,
for
example,
g)
Turn the emission
off
and increase the limit value
by
aluminum foil
(do
not short circuit).
0.1 A.
b)
Set
the
offset
correction
on
the control unit to
zero,
<emiss>
«E-PROT4
:
+
0.1 A
<amplif>
«OFFSET»
:
«O,CO»
h)
Turn
the
emission
on.
c)
Enter the highest filter value,
il
Repeat steps
g) and
h)
until the «Emission
error»
message
goes
out.
<amplif>
«FILTER»
:
800 ms»
d)
Select the
mass
range.
CAUTION:
If
the limit value resulting from the
above procedure
is
abnormally
<amplif>
«RANGE»
:
«E-6» or «E·7»
high, there could
be an
error
in
the
ion
source,
the vacuum
conditions
e}
Adjust the
zero
point
for
the electrometer preamplifier
or in
the control unit itself.
You
from the trimmer potentiometer (with screwdriver
must troubleshoot the cause
of
a
through the hole next
to
the control cable)
too-high limit value to prevent the
filament from buming out.
k)
If
the filament
is new,
leave it
on for
several
hours
and
then adjust the limit value to
as low
a
value
as
f)
Select
a
sensitive
mass range.
<amplif>
«RANGE»
:
«E-8»
or «E-9»
g)
Check
the zero
point
and
correct
if
necessary'
5.1.5 Aligning
the
quadrupole electronics
h)
Repeat steps
f)
and
g),
selecting more sensitive
mass
ranges.
As
vibrations could interfere with the
CAUTION:
Before
starting
your
measurement
adjustment,
we
recommend removing the screwdriver
system,
refer
to the information
given
after making the adjustment
and
then checking
the
in
the operating instructions
for
the
offset
quadrupole electronics (12].
a)
Set the
<filament
selection> switch to <remote>
and the
<
polarity>
to
<
+
> (see
11
2)
).
ŒO
b)
Check the <TUNE> setting
and
,if
necessary
,
5.1.4 Optimizing
the
emission
current limit
values
optimize it according to section 6.2
in
the operating
CAUTION:
Before
starting your OMG system,
instructions
{12].
refer
to the information given
in
the
operating instructions
for
the
RF
5.1.6 After adjustments
to the
measuring
system
generator (10, 11].
or
component
replacement
Optimize the emission current limit values
for
normal
operation («E-PROT»). The emission
is
turned
off
We recommend carrying out
an
initial start
up
routine
as
immediately any time this value
is
exceeded,
for
described above after the
ion source
has
been realigned,
example,
as
a
result
of
poor
vacuum
or
another
error
the filament replaced,
a
component replaced, etc.
situation. Choose the limit value
as low as
possible. This
will
provide optimum protection
for
your filament:
a)
Tum the emission
off.
<filam>
(LED
<filam>
dark)
b)
Make
sure
the
vacuum
is
i10
mbart,
c)
Turn the
emission
on.
<filam>
(LED
<filam>
Ughts)
d)
If
the
«Emission
error»
message
does
not appear, tum
the emission
off
and reduce the limit value
by 0.1 A.
If
the error
message appears, continue from step
g),
<emiss>
«E-PROT»
:
-
0,1 A
18
Bedienung
aMs42tog
opm
Advertisement
Table of Contents
