Function/Range Switch: selects the function (voltmeter, ammeter,
or ohmmeter) and the range for the measurement.
COM Input Terminal:Common ground, used in ALL measurements.
V
Input Terminal: for voltage or resistance measurements.
200 mA Input Terminal: for small current measurements.
10 A Input Terminal: for large current measurements.
Low Battery LCD: appears when the battery needs replacement.
Precautions for Voltage Measurements
Plug the black test lead into the COM jack.
Plug the red test lead into the
V jack.
Set the function/range switch to either
DC volts in the upper left, or
AC volts in the upper right.
If you do not know the approximate voltage about to be measured, use
the largest voltage range available.
Connect the free ends of the red and black test leads ACROSS the
device to the measured. Voltage is always measured with the meter
in PARALLEL with the device.
If the LCD displays either "1." or "-1." with all other digits blank,
the voltage is beyond the selected range. Use the switch to select a
larger range.
Once you know the approximate voltage across the device, then use the
switch to select the lowest voltage range that will still accomodate
the voltage across the device. For example:
Range
Actual value
Display
Comments
1000 VDC
18.75 V
19
Reduce range
200 VDC
18.75 V
18.8
Reduce range
20 VDC
18.75 V
18.75
Correct range
2 VDC
18.75 V
1.
Overload - increase range
Precautions for Current Measurements
Turn the power off to the device and discharge
any capacitors!
Plug the black test lead into the COM jack.
Plug the red test lead into either the
200 mA jack for small current measurements, or the
10 A jack for large current measurements.
If you do not know the approximate current about to be measured, use
the 10 A jack.
Set the function/range switch to either
DC amperes in the lower right, or
AC amperes in the middle right.
Break open the circuit at the point where you want to measure the current
by removing one of the wires. Connect the free end of the red test lead
to one place at which the wire was attached. Connect the free end of the
black test lead to the other place at which the wire was attached. Current
is always measured with the meter in SERIES with the device. If you do
not understand the difference between SERIES and PARALLEL, ask your TA.
Using the current meter incorrectly will blow the fuse or damage the meter.
(It will also cost you points on your lab writeup.)
Reapply the power to the device.
If the LCD displays either "1." or "-1." with all other digits blank,
the current is beyond the selected range. Use the switch to select a
larger range.
Once you know the approximate current through the device, then use the
switch to select the lowest current range that will still accomodate
the current through the device.
Turn the power off to the device before removing the meter from the
circuit.
Precautions for Resistance Measurements
Turn the power off to the device and discharge
any capacitors!
Plug the black test lead into the COM jack.
Plug the red test lead into the
V jack.
Set the function/range switch to ohms
( ) in the
lower left.
If you do not know the approximate resistance about to be measured, use
the largest range available.
Connect the free ends of the red and black test leads ACROSS the
device to the measured. Resistance is always measured with the meter
in PARALLEL with the device.
If the LCD displays either "1." or "-1." with all other digits blank,
the resistance is beyond the selected range. Use the switch to select a
larger range.
Once you know the approximate resistance of the device, then use the
switch to select the lowest range that will still accomodate
the resistance of the device.
