Tempo MM200 Manual De Instrucciones página 9

• Automatic Power Off: To extend battery life, the meter will shut itself off after approximately
30 minutes of inactivity. To restore power, press either the SELECT, CREST, or REC button or
turn the selector to OFF and then back on. To disable this feature, press SELECT while turning
the meter on.
Using the Features (cont'd)
AC Measurement
• Disabling the Beeper: Hold down the RANGE button while turning the meter on to temporarily
AC measurements are usually displayed as RMS (root mean square) values. The RMS value is equal to
disable the beeper feature. Turn the selector to OFF and then back on to enable the beeper.
the value of a DC waveform, which would deliver the same power if it replaced the time-varying wave-
form. Two AC measurement methods are average-responding RMS calibrated and true RMS-reading.
AC Measurement
The average-responding RMS calibrated method takes the average value of the input signal after full
AC measurements are usually displayed as RMS (root mean square) values. The RMS value
wave rectification, multiplies it by 1.11, and displays the result. This method is accurate if the input
is equal to the value of a DC waveform, which would deliver the same power if it replaced the
signal is a pure sine wave. The DM-200A and DM-210A are average-responding meters.
time-varying waveform. Two AC measurement methods are average-responding RMS calibrated
The true RMS-reading method uses internal circuitry to read the true RMS value. This method is accu-
and true RMS-reading.
rate, within the specified crest factor limitations, whether the input signal is a pure sine wave, square
The average-responding RMS calibrated method takes the average value of the input signal
wave, triangle wave, half wave, or signal with harmonics. The ability to read true RMS provides much
after full wave rectification, multiplies it by 1.11, and displays the result. This method is
more measurement versatility. The DM-510A is a true RMS meter.
accurate if the input signal is a pure sine wave. The MM200 is an average-responding meter.
The Waveforms and Crest Factors table shows some typical AC signals and their RMS values.
Waveforms and Crest Factors
Waveform
RMS Value
Average Value
Crest Factor*
(x)
* The crest factor is the ratio of the peak value to the RMS value; it is represented by the Greek
letter x.
100 100
90 100
1.414 1
9
MM200A
100 100
87 64
1.73 2