Changing Line Voltage; Changing Line Frequency; Battery Replacement; Post.repa¡R Procedures - Datron 1061 Calibration And Servicing Handbook

51
sEcTtoN
4
INTE
RNAL ADJUSTMENT
PROCEDUR
ES
4.1
ALTERATTON
OF LINE VOLTAGE
AND
LINE 4.2
BATTERY
REPLACEMENT
FREOUENCY
2,
3.
4.
5.
6.
7.
t
i r
I iiI
.u
The
instrument ¡s set
to
50H2, 205V
to
255V
supplies
unless Option
80. 81
or 82 is
specified. This
information
is
carried
on the
¡nstrument
identif ication
label located on the
rear
panel. Alteration
to
a different
line
voltage/line frequency
may
necessitate
an instrument
recalibration.
4.1.1
Changing Line Voltage
1.
Disconnect power
and
all
signal
input/output
leads.
2.
Remove the lower cover.
3.
Locate
the
l¡nk(s) connecting
the split primary
on
the
printed circuit board in front of the
toroidal
line
transformer', Fig.
2.1
and Drawing
No 400291
4.
t
t:X."ff!111n:-
Bemove
LKI
(link
1)
and
f
it
LK2
230V Operation:-
Remove
links LK2 and LK3,
and
1¡1
¡ç1
[1J
.
5.
Amend instrument identif ication
label.
6.
Replace lower
cover.
7.
Replace
power
fuses
with
160mA
anti-surge
(230V1
or 500m4
anti-surge
(1
15V).
8.
Carry out the Specification Verification
tests
(Sec-
tion 8,
User's
Handbook)
and recalibrate
if
necessary.
4.1.2
Changing
Line
Frequency
1.
Disconnect power
and
all
signal
input/output
leads.
2.
Remove the
top
cover.
3.
4OOHz -Operation:- Remove
link
LK5 and fit
¡¡7[1]
on the Digital
assembly,
(Drawing
No.
400329).
50/60H1
-Operation:- remove
link
LK7
and
fit
¡¡5t1.|
on the Digital
assembly
(Drawing
No.
400329).
4.
Place instrument
into
HOLD. Adjust
L2
(DiSital
assembly) so that Tp7 is
l.OSV
f.0.03V wirh
respect
to
Digital Common (Tp2g).
NOTE:
ïhis
signal contains about 200mV
peak-to-peak
high frequency
noise.
5.
Amend instrument identif ication
label.
6.
Replace the top
cover.
7.
Carry
out
the
Specif
ication
Verif
ication
tests
(Sec-
tion 8,
User's
Handbook)
and recalibrate
if
necessary.
[1]tinL,
should
be 22
SWG
TlN.Cu wire with
silicone
rubber
sleeving.
The battery
should
be
replaced
on
or
before
the
date indicated on the
rear panel instrument identification
label.
To
retain
the
calibration memory,
the
instrument
must be
powered-up
during
replacement. Therefore great
care
must
be taken
due
to
voltages
up
to
260
volts
being
present
inside the instrument.
Remove
top
cover
and
locate
battery on
the
Digital
assembly (see Fig. 2.1).
Power-up
instrument,
Desolder
battery
at end
of
tags
and
remove
from
clip.
Replace
with
new
battery, (Datron
Part
No.920049)
positive terminal to
resistor.
Replace
top
cover.
Amend instrument identification label (Current
date
+
5 years).
Carry
out the
Specification Verificat¡on tests
(Sec-
tion 8,
User's
Handbook) and
recalibrate if
necessary.
4.3
POST.REPAIR
PROCEDURES
Apart from the
RMS
Module (which
is
available only
from
Datron),
all
integrated
circuits and
semiconductor
devices are standard manufacturers'
products, and
special
selection
is
unnecessary.
During
manufacture
ærtain
resistors
are
selected
in
value
(FSV
=
Factory
Selected
Value)
to
accommodate
circuit component
tolerances, or
to
bring the
desired setting
of
a
preset control
to
the
middle
of
its
adjustment
range.
The thermal
tracking
of
the
DC Preamplifier is part-
icularly ¡mportant,
to
ensure
a
low order
of
zero drift
with
variations
of
temperature.
This rather time
consum-
ing procedure is
carried
out initially
during
manufacture,
and need
only
be
repeated
following
replacement
of
O12
or
any
component
associated
with the
temperature
com-
pensation
circuitry.
NOTE:
A
routine calibration
as
detailed
in
Section
1 should be
carried
out after completion of
the
following
procedures.
CAUTION
:
Up
to
260 volts is
present inside
the
¡nstrument.
Personal
contact
with
these
points may
result
in injury.