Decibel Measurement; Continuity Test - Minipa ET-3021 Manual De Instrucciones

D. Decibel Measurement
1. Connect the red test lead to + AVΩ terminal and the black test
lead to -COM terminal.
2. Select the rotary switch to one ACV range. If the magnitude of
the signal is not known, select the highest range and then reduce
until a satisfactory reading. Remember that the reading will be
more accurate is it is taken in the upper half of the scale.
3. Turn off the power of the circuit under test and discharge all capa
citors before connecting the test leads to the points to be masured.
4. Use the dB scale to make reading, rather than the scale of ACV.
Note:
• For measurement of an absolute value in dB, the circuit impe
dance must be 600Ω. In this impedance value, 0dB is equivalent
to 1mW dissipated over this impedance (equivalent to 0.775
Volts over 600Ω).
• To measure the full scale of 10V AC dB (-10dB to 22dB) the rea
ding will be direct. For measurements in the range 50V AC should
add the value read 14dB. For measurements in the range 250V
AC should add the value read 28dB and measured in the range
1000V AC should add the value read 40dB.
• Case you are measuring decibel of a signal that has a level DC,
place a capacitor of 0.1 mF (or larger) in series with this signal,
to eliminate this DC level.
E. Continuity Test
1. Connect the red test lead to +AVΩ terminal and the black test
lead to -COM terminal.
2. Select the rotary switch to position
3. Turn off the power of the circuit under test and discharge all capa
citors before connecting the test leads to the points to be masured.
4. Touch the test leads on the circuit to be tested. Case the resistence
between points to test is less than the threshold (approx 100Ω),
a beep is emitted.
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