Velleman DVM4x00 Series, Руководство пользователя

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•
When measuring DC offset of an AC voltage, measure the AC voltage first and
select a range for the DC offset equal to or higher than the AC range to increase
accuracy.
7.2 Resistance measurements
Do not perform resistance measurements on live circuits.
• Connect the red test lead to the "VΩ Hz " jack and the black lead to the
"COM" jack.
•
Set the rotary switch to "
Ω
”. When necessary, press the SELECT button until MΩ
is shown on the display.
•
Press the RANGE button to manually select the range.
•
Connect the test probes to the source being measured.
•
The measured value appears on the LCD display.
•
Notes:
o
Never perform resistance measurements on a live circuit and make sure all
capacitors are completely depleted.
o
To increase accuracy when measuring low resistance values, first hold the tips
of the measuring probes together to determine the resistance value of the test
leads. Subtract this value from the measured value of the circuit.
o
For resistance measurements above 10MΩ the meter needs a few seconds to
stabilize the read-out.
o
Should the measured resistance exceed the current range or in case of an open
circuit, the display will show “OL”.
7.3 Continuity measurements
Do not perform continuity measurements on live circuits.
•
Connect the red test lead to the "VΩ Hz " jack and the black lead to the
"COM" jack.
•
Set the rotary switch to .
•
Press the SELECT button to select continuity test .
• Connect the test probes to the source being measured.
• When the measured resistance is less than 40Ω a continuous beep is produced
and the resistance value is showed on the display. Should the measured
resistance exceed the current range or in case of an open circuit, the display will
show “OL”.
Nota: Never perform continuity measurements on a live circuit and make sure all
capacitors are completely depleted.
7.4 Diode measurements
Do not perform diode measurements on live circuits.
• Connect the red test lead to the "VΩ Hz " jack and the black lead to the
"COM" jack.
•
Set the rotary switch to .
•
Press the SELECT button to select diode test .
• Connect the red test probe to the anode of the diode and the black test probe to
the cathode.
•
The meter shows the forward voltage drop of the diode. When the diode is
connected with a reversed polarity, the display shows “OL”.
Notes:
o
Never perform diode measurements on a live circuit and make sure all
capacitors are completely depleted.
o
Measuring diodes that are part of a circuit might produce faulty results.
Consider unmounting from the circuit.