732A
Table
2“2.
Rear
Panel Features (cont)
ITEM
FEATURE NAME
DESCRIPTION
7
Fuse
holder
AC
line
fuse
holder.
8
Power
connector
lEC 3-wire
receptacle,
for
ac line
power connection.
See item
3
for
specified
ac
line
voltage.
2-20,
Backup
Operating
Power
2
-
2
\, If
ac line
power
fails or
drops
more
than
30%
below
the
nominal value,
the internal
battery
automatically
maintains operation. Set
the
rear
panel
BATTERY
OPR
switch
to on to
enable
the internal
battery*
When
line power fails,
the AC PWR
indicator
goes out,
but
the
IN CAL
indicator
remains on* The unit
will
continue
to operate normally,
until the battery
discharges*
When
the battery is discharged,
the
IN
CAL
indicator
will go
out.
When
ac
power
is restored,
the
BTRY
CHG indicator
illuminates,
until
the
battery
is
fully
charged,
The IN CAL indicator will not
illuminate.
This indicates
that
the standardization of the
instrument
must
be
reverified
before the 732A
is used. The battery
voltage
may be
measured
at the POWER INPUT
jacks
with a high
impedance multimeter,
such as Multimeter A,
Table
4-1.
2-22.
Battery
Charging
CAUTION
PERMANENT
BATTERY
DAMAGE
WILL
RESULT
IF THE BATTERY
IS
ALLOWED
TO
DISCHARGE
BELOW 19
VOLTS. THE
DEGREE
OF DAMAGE
IS
A
FUNCTION
OF
THE DEPTH
OF OVER-DISCHARGE
AND
THE BATTERY
TEMPERATURE.
2-23.
Under
normal
operation,
battery
life
should
exceed
5
years.
For
best battery life, minimize
the number
of charge/ discharge
cycles and
avoid
deep (<19V)
discharge*
2-24,
if the battery is fully
discharged,
24 hours
is
required
to fully recharge the battery when operating
the
732A from
ac line
power,
if the battery is not fully
discharged, the charging
time will
be
less, but
always
in
excess of the discharge time. When the battery is
charging, the
BTRY
CHRG indicator
glows to
indicate
charging activity and turns off when the battery is fully
charged.
2-25.
IN
CAL Indicator
and RESET Terminal
2-26.
If the IN CAL indicator does
not illuminate
(ac
power
lost, battery dead or
turned
off),
the
output
of the
732 A
may
not
meet the
specifications
listed
in Section I.
The RESET terminal, located behind the front panel, is
used to restore the IN CAL indicator to the ON condition.
See
Section 4
for
the
reset
procedures.
Before
resetting the
indicator,
apply
power (ac
line
or
low
voltage
external ac
or
dc),
allow' a
stabilization
period
of
24 hours, then
check
the 732A
to
insure that
the
various
outputs are within
specification.
2-27.
Portability
2-28.
The 732A
is
portable and
operational
at
ambient
temperatures
between
Oand
40''C
(32
to
104"^
F).
Norma!
handling
and
transportation
will not
alter
accuracy
or
stability if
power is maintained
by the
internal
battery
or
through
the externa!
power
connections.
The
instrument
may be
used
immediately
after
transportation,
provided
that
the IN
CAL
indicator
is
illuminated
and that the
instrument
has not
been
exposed
to ambient
temperatures
beyond
the
normal
operating
range
(23
±
5^C).
2-29.
Guarded
Operation
WARNING
LETHAL
VOLTAGES
MAY
BE
PRESENT
WHEN
OPERATING THE
732A WITH
THE
GUARD AND
CHASSIS
GROUND
CON-
NECTIONS
SEPARATED.
A
MAXIMUM
POTENTIAL
DIFFERENCE
OF
60V
RMS
MAY
APPEAR
BETWEEN
ANY COMBINATION
OF
THE
GUARD
TERMINAL,
CHASSIS
GROUND,
REFERENCE
STANDARD
OUTPUT,
OR OVEN
TEMPERATURE
THERMISTOR
OUTPUT.
IF
THIS LIMITA-
TION
IS
EXCEEDED,
DAMAGE
TO THE
INSTRUMENT
MAY
RESULT.
2-30.
The
732A is equipped with a
guard that
isolates
the internal circuitry
from chassis
and earth
ground, A
GUARD terminal is
provided
on
the
front panel.
When
properly used the
guard can greatly reduce
errors caused
by common mode voltages. In
general,
guarded
operation
will be
necessary
under the following
conditions:
1.
When
a potential exists
between
equipment
powder
line
grounds.
2.
When long
connection leads
are used to
connect
a
high
impedance load.
3.
When
operating
the instrument in
the presence
of high level radiated noise.
2-5
To Next Page
Loading...
