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EX420-EU_ENG
V3.1
6/09
8
AC CURRENT MEASUREMENTS
CAUTION:
Do not make current measurements on the 20A scale for longer than 30
seconds. Exceeding 30 seconds may cause damage to the meter and/or the test leads.
1. Insert the black test lead banana plug into the negative
COM
jack.
2. For current measurements up to 4000µA AC, set the
function switch to the yellow µA position and insert the
red test lead banana plug into the
µA/mA
jack
3. For current measurements up to 400mA AC, set the
function switch to the yellow mA position and insert the
red test lead banana plug into the
µA/mA
jack.
4. For current measurements up to 20A AC, set the
function switch to the yellow 20A range and insert the
red test lead banana plug into the
20A
jack.
5. Press the SELECT button to indicate “
AC
” on the
display.
6. Remove power from the circuit under test, then open up
the circuit at the point where you wish to measure
current.
7. Touch the black test probe tip to the negative side of
the circuit.
Touch the red test probe tip to the positive side of the
circuit.
8. Apply power to the circuit.
9. Read the current in the display.
RESISTANCE MEASUREMENTS
WARNING:
To avoid electric shock, disconnect power to the unit under test and
discharge all capacitors before taking any resistance measurements. Remove the
batteries and unplug the line cords.
1. Set the function switch to the green
position.
2. Insert the black test lead banana plug into the negative
COM
jack.
Insert the red test lead banana plug into the positive
jack.
3. Press the SELECT button to indicate
on the display.
4. Touch the test probe tips across the circuit or part under test.
It is best to disconnect one side of the part under test so the
rest of the circuit will not interfere with the resistance
reading.
5. Read the resistance in the display.