Power quality – KYORITSU 6310 Instruction Manual User Manual
Page 206
11. Power quality KEW6310
11.1
KEW6310
11. Power Quality
Power Quality
Waveform
Symptoms
Adverse effects
Harmonic
Inverter and thyristor circuits
(phase-control circuit) are used
for the control circuit of general
devices; these circuits affect
currents and causes harmonics.
Burnout of capacitors and
reactors, buzzes from trans-
formers, malfunction of circuit
beakers, flicker in screen or
noises on stereos due to
currents with harmonic
components.
Swell
Inrush currents occur when
switches for power lines are
on, and then voltages
increase instantaneously.
Dip
Inrush currents occur when
motor loads are activated, and
dip in current occurs.
Int
Power supply is interrupted
for a second due to lightning
strikes.
Shutdown of devices or
robots or reset on PC and
business machines may be
caused.
Transient,
Over-voltage
(impulse)
Contact failure at a circuit
breaker, magnet or relay.
Damage to a power source or
reset of the device may occur
due to a drastic voltage
fluctuation (spike).
Inrush current
Instantaneous large currents
(surge) flow on devices with a
motor,
incandescent lamp and
flat capacitor when powering
them on.
Influences on welded contacts
for Power switch, blowing fuse,
trip on breaker,
rectifier circuit
and fluctuations in power supply
voltage may occur.
Unbalance
rate
Heavy loading on specific phase
due to fluctuations in load of
power line or drastic extension
of installations. Distortions of
voltage / current waveforms, dip
and negative sequence voltages
are caused.
Influences on voltage, current,
motor operation occur; negative
sequence voltage and
harmonics occur.
Flicker*
Too much load is caused on
certain phases due to increase
and decrease of the loads
connected to each phase such
as supply lines or heavy use of
specific equipments, as a result,
Distortions on voltage and
current waveforms, dip and
reversed voltages are observed.
Unbalanced or reversed
voltages and harmonics occur
and result in motor unstability,
trip of 3E circuit breaker or
heating due to overload.
* Flicker measurement function is only available with ver.2.00 or later.
RMS
RMS
RMS