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10.1
10.1
10.1
10.1 General
General
General
General Description
Description
Description
Description
Harmonics are any “non-linear” current or voltage in an electrical distribution system.
With these harmonics flowing into the power system, it will affect the reliability of the
transformers and protection relays, and it will accelerate the ageing of metalized
polyester film, increase the power loss of transmission, and disturb communication or
measurement accuracy of instruments.
PMAC770 provides up to 31
st
harmonics analysis which is strong helpful for power
quality analysis.
10.2
10.2
10.2
10.2 THD
THD
THD
THD
PMAC770 measures voltage and current harmonic up to 31
st
, and calculates THD,
TOHD (Odd) and TEHD (Even).
Users can read THD data (%) from the LCD or communication. For example, the data
is 20.00, the actual THD value is 20.00%
10.3
10.3
10.3
10.3 Harmonic
Harmonic
Harmonic
Harmonic Ratio
Ratio
Ratio
Ratio for
for
for
for Voltage
Voltage
Voltage
Voltage
PMAC770 measures up to 31
st
voltage harmonic. Users can read 2~31
st
voltage
harmonic (%) from the LCD or communication. For example, the data is 10.00, the
actual harmonic value is 10.00%
HRW Limited
Ph +852 2546 7402 - Fax +852 2546 7403 - [email protected] - www.hrw.hk