Safety; Controls - Datron 1061A User Handbook Manual

Safety
The
1061
and
1071 voltmeters are
designed
to be
Class
1
equipment
as
defined
in
IEC
Publication
348
and
UL
1244 concerning
safety
requirements.
Protection
is
assured by
a direct
connection
via the
power
cable
from ground
to
exposed metal parts
and
WARNING:
ANY
INTERRUPTION OF THE PROTECTIVE
GROUND
CONDUCTOR
INSIDE
OR
OUTSIDE
THE INSTRUMENT OR
DISCONNECTION OF
THE PROTECTIVE
GROUND
TERMINAL MAY
MAKE THE APPARATUS DANGEROUS.
INTENTIONAL INTERRUPTION
IS
PROHIBITED.
THE TERMINALS MARKED WITH THE
SYMBOL CARRY THE
POTENTIAL
OF THE
internal
ground
screens.
The
line
connection must
only
be
inserted in a
socket outlet
provided with
a protective
earth
contact
and
continuity of the
ground conductor
must
be assured
between
the socket
and
the
instrument.
SOURCE
UNDER
TEST.
THESE TERMINALS
AND ANY OTHER CONNECTIONS TO
THE
SOURCE
COULD CARRY LETHAL VOLTAGES.
AT
NO
TIME
SHOULD
THESE
CONDUCTORS
BE
TOUCHED
DURING
A
TEST
OF HIGH
VOLTAGES.
IF
DIFFICULTY
IS
FOUND WITH
THE
TEST,
ENSURE THAT THE SOURCE
IS
RENDERED
SAFE BEFORE ATTEMPTING
TO
IMPROVE CONNECTIONS.
Controls
Fig
2.1
Front panel
Line on/off ('Power') switch
When
set
to the off position, this
switch
isolates
the
instrument
from
the line
supply.
When
switched
to the
on
position, the
instrument
powers up and
automatically
selects
its
DC
1000V
range.
After
l
/
2
hour,
the
instrument
is
near
its
full
specification,
but should be
left
on
for 2
hours
before use
if
full
accuracy
is
required.
Function keys
The
four keys
-
T,
'kO',
'AC'
and 'DC'
-
provide
the
means
to
select
the
mode
of operation of the
instrument
and
contain
LED
indicators that
light
to
show
the selected function,
i.e.
if
the indicators
in
the
T
and 'DC' keys
are
lit,
the
instrument
is
set
to
measure
DC
currents.
'Input zero'.
This facility
is
available
on
all
DC
voltage
and
Ohms
ranges,
by manual or systems
operation.
When
the 'Input Zero'
key
is
pressed, the
DVM:
a)
accepts the
measured input as a zero
offset for
the
range selected,
providing
it
does not
exceed
approx
1
.5% of
full
range.
b) stores the offset
value
in
non-volatile
memory.
c)
compensates
ALL
SUBSEQUENT READINGS
taken
on
that
range
by
the stored offset
value,
.
until the
user redefines the
input
zero.
If
the
measured input
offset
exceeds 1.5% of
full
range
from
the
calibrated
DVM
zero,
no offset
is
stored
and the
Err 4 message
is
displayed.
A
separate
zero
offset correction
is
stored for
each
range.
When
the
DVM
is
in
'Auto' during the
Input Zero routine,
all
ranges are
zeroed
automat-
ically in
ascending
order.
f.
l
Li
v
2-2