– 6 –
4 AC CURRENT MEASUREMENT
!
WARNING: Remove all power from circuit being tested when check-
ing current. When using the 10A range do not connect to the circuit
for more than 60 seconds and wait 10 minutes between 10A meas-
urements.
4-1
Plug the red test lead into the mA jack and the black test lead into the COM
jack. If the current being measured is between 400mA and 10A insert the
red test lead into the 10A jack.
4-2
Set the DC/AC switch so that
AC
is displayed on the LCD.
4-3
Set the range switch to the desired
A
current setting. If you are unsure of
the value being measured, select the highest range and reduce until a
satisfactory reading is obtained.
4-4
Remove power from the circuit that is to be measured. Open up the circuit
and connect the black lead to one side and the red lead to other side of
the circuit so that the test leads are in series with the load to be measured.
4-5
Apply power to the circuit.
4-6
Read the displayed current.
4-7
Remove power to the circuit being measured and disconnect test leads.
NOTE: If changing range switch to or from the 10A position first disconnect
power and test leads from the circuit being tested. Repeat the above
steps using the correct input jack and range switch position.
5 RESISTANCE MEASUREMENT
!
WARNING: Remove all power from circuit being tested when check-
ing resistance. Discharge any charged capacitors. Never connect
the probes to any voltage while the range switch is set to
Ω
.
5-1
Plug the red test lead into the V
Ω
jack and the black test lead into the
COM jack.
5-2
Set the range switch to the desired
Ω
setting. If you are unsure of the
resistance being measured, select the highest range and reduce until a
satisfactory reading is obtained.
5-3
Attach the test leads to the circuit.
5-4
Read the displayed resistance.
NOTE:
1. If you short the test leads together you will notice a small resistance value.
This is due to the meter and test leads internal resistance. When
measuring a small resistance subtract this value to obtain a more precise
value.
2. When using the 400
Ω
range the continuity buzzer will sound if the
resistance being measured is less than 50
Ω
.
