B&K 281 - Page 13

g-
. assembly must be connected to the 1A jack 4.
h.
When
using
the
ТА
current
range,
the
(+)
tip
of
the
test
probe
Refer
to
Table
1
for
interpretation
of
the
digital
readout
obtained.
- AC CURRENT MEASUREMENTS
a.
b.
С.
g
Set the FUNCTION switch to the ACA position.
Switch out the 100 Kohm resistor іш. the test probe.
Set
the
RANGE
switch
to
the
desired
position.
If
in
doubt
about
the
magnitude
of
the
current
to
be
measured,
use
the
highest
current
range
and
then
adjust
the
RANGE
"s
as
required
to
obtain
a
satisfactory
reading.
If
the
IA
position
of
the
RANGE
switch
is
selected,
the
(+)
pin
of
the test
probe
assembly
must
be
connected
to
the
1A jack.
When
connecting
the
multimeter
for current
measurements
remove
the
power
from
the
circuit
being
tested
while
the
connections
are
being
made.
Do not make
or
break
series
connections
to
the
circuit
under
test
with
power
applied.
If
the
magnitude
of
the
current
being
measured
exceeds
twice
the
value
of
the
range
selected,
the
over
range
circuitry
is
energized,
causing
the
first
digit
to
remain
of
and
the
second
and
third
digits
to
flash
on
and
off
together.
When
this
occurs,
immediately
remove
power
from
the
circuit
under
test
and
select
a
higher
current
range
before
proceeding
further.
Refer
to
Table
1
for
interpretation
of
the
readings
obtained.
RESISTANCE MEASUREMENTS
CAUTION
Do not attempt to measure resistance in a circuit in which the power
is applied. Remove power and make sure that all capacitors are
discharged before attempting in-circuit resistance measurements.
Set the FUNCTION switch to the OHMS position.
If the OHMS circuit doesn’t work, you may have burned out the
ohms circuit fuse (F101) by making a resistance measurement in a
“hot” circuit. To replace it, remove thé two screws retaining the
cover and carefully lift it off. Replace F101 (Figure 2) with the
spare fuse clipped to the rear panel on the inside of the unit.
. Switch out the 100 Kohm resistor in the test probe.
Set the RANGE switch to the desired position. Connect the test leads
across the resistance to be measured.
. If the resistance value being measured exceeds twice the value of the
range selected, the overrange circuitry is energized, causing the first
digit to remain off and the second and third digits to flash on and
off together.
Refer to Table I for proper interpretation of the readings obtained.
11
atm,
——