Measuring Dc/Ac Current - Radio Shack 22-813 Owner's Manual

o o
WARNING
• This voltage (692.8V
AC) exceeds the
meter's rating.
Therefore, you should
not connect the meter
to this circuit or to any
equipment connected
to the circuit. Doing
so could present a
dangerous shock
hazard to you, and
could also damage
the meter.
• When the meter is set
to its current
measurement
function, do not apply
voltage directly
across terminals. You
must connect the
meter in series with
the circuit.
CAUTION
• When the meter is set
to its current measure-
ment function, never
connect the test leads
across a voltage
source. Doing so can
damage the meter or
the circuit under test.
The maximum input
limit for AC/DC current
measurement is 10A.
• If you do not know the
amount of current in
the circuit you are
measuring, always
connect the red test
lead to .
+ 10A MAX
14
Three-phase industrial circuits are extremely
powerful. You can be burned severely and
even killed if you create an accidental short
in these panels.
Before measuring voltages, put on
protective clothing – a face shield and
fireproof gloves and upper body protection is
required. If you do not have this protection,
DO NOT MEASURE THESE CIRCUITS.
Most 3-phase power circuits are rated by
their line-to-line voltage. This voltage is
higher than the line (or phase) to ground
voltage. To determine if a line-to-line 3-
phase voltage exceeds the rating of this
meter, multiply the rated line-to-ground
voltage by 1.732 (the square root of 3). For
example, if the rated line-to-ground voltage
is 400 volts, the line-to-line voltage is 400
o
1.732 = 692.8 V AC.
M DC/AC C
EASURING
To measure AC or DC current, you must
break the circuit and connect the test leads
to two circuit connection points. The
connection must be in series with the circuit
o
under test.
1. Disconnect power from the circuit you
will test and discharge all capacitors.
2. Rotate the function dial to
3. Repeatedly press
SELECT
or AC. appears for AC current
measurement.
4. Connect the black test lead to one of
the two connection points on the
broken circuit.
URRENT
.
mA/A
to select DC