DMR35-ACA.A01.D0

5 Page 9 of 11

DMR35-ACA/mA Series

AC Ammeter

www.murata-ps.com

(CONTINUED):

RMS MEASUREMENT MODE VS. AVERAGE MEASUREMENT MODE.

Frequency Response, Crest Factor, and Accuracy

DMR35 AC meters are designed to accurately measure signals typically seen in 50/60 Hz AC systems. For sinusoidal input waveforms, the

measurement error typically varies less than

±1 % over the range of 20 Hz to 120 Hz, as shown in the graph below.

Since more complex waveforms contain higher frequency components and varying crest factors, the expected accuracy can vary considerably as a

function of both frequency and waveform. The table below shows some typical accuracies for RMS measurements of the following waveforms at

specified frequencies.

Waveform

Crest

Factor

Typical % Error at Given Frequency 1

30 Hz

60Hz

120 Hz

240 Hz

400 Hz

Sinusoid

0

1

1.414

0.0%

0.1%

0.4%

2.2%

4.9%

Square wave

0

1

1.000

-0.4%

-1.0%

-2.0%

-3.9%

-4.9%

Triangle

0

1

1.732

0.1%

0.1%

0.3%

1.8%

4.1%

Phase-

controlled

Sinusoid –

leading 50%

0

1

2.000

-0.7%

-1.5%

-2.6%

-6.0%

-12.4%

1 DMR35-ACA1 response, measured against calibrated Fluke 8845A RMS digital multimeter

-30%

-25%

-20%

-15%

-10%

-5%

0%

5%

10%

10

100

1000

Frequency (Hz)

Typical Measurement Error vs. Frequency,

Sinusoidal Input