Hioki PQ3198, Instruction Manual

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Manual event function
Functionality for generating events when the MANU EVENT key is pressed and recording
the measured value and event waveform at that time. In this way, events can be generated
as a snapshot of the system being measured. Use this functionality when you wish to
record a waveform but cannot find another event that defines the desired phenomenon or
when you wish to record data manually to avoid the generation of too many events.
Reactive power
Power that does not perform actual work, resulting in power consumption as it travels
between the load and the power supply. Reactive power is calculated by multiplying the
active power by the sine of the phase difference (sin
θ
). It arises from inductive loads
(deriving from inductance) and capacitive loads (deriving from capacitance), with reactive
power derived from inductive loads known as lag reactive power and reactive power
derived from capacitive loads known as lead reactive power.
Reactive power demand
The average reactive power used during a set period of time (usually 30 minutes).
Active power
Power that is consumed doing work.
Active power demand
The average active power used during a set period of time (usually 30 minutes).
Power factor (PF/DPF)
Power factor is the ratio of effective power to apparent power. The larger the absolute
value of the power factor, the greater the proportion of effective power, which provides the
power that is consumed, and the greater the efficiency. The maximum absolute value is 1.
Conversely, the smaller the absolute value of the power factor, the greater the proportion of
reactive power, which is not consumed, and the lower the efficiency. The minimum abso-
lute value is 0.
For this device, the sign of the power factor indicates whether the current phase is lagging
or leading the voltage. A positive value (no sign) indicates that the current phase is lagging
the voltage. Inductive loads (such as motors) are characterized by lagging phase. A nega-
tive value indicates that the current phase is leading the voltage. Capacitive loads (such as
capacitors) are characterized by leading phase.
The power factor (PF) is calculated using rms values that include harmonic components.
Larger harmonic current components cause the power factor to deteriorate. By contrast,
since the displacement power factor (DPF) calculates the ratio of effective power to appar-
ent power from the fundamental voltage and fundamental current, no voltage or current
harmonic component is included. This is the same measurement method used by reactive
power meters installed at commercial-scale utility customers' facilities.
Displacement power factor, or DPF, is typically used by the electric power system, although
power factor, or PF, is sometimes used to measure equipment in order to evaluate effi-
ciency.
When a lagging phase caused by a large inductive load such as a motor results in a low
displacement power factor, there are corrective measures that can be taken to improve the
power factor, for example by adding a phase advance capacitor to the power system. Dis-
placement power factor (DPF) measurements can be taken under such circumstances to
verify the improvement made by the phase advance capacitor.
Continuous event
function
Functionality for automatically generating the set number of events in succession every
time a target event occurs. Events after the initial event are recorded as continuous events.
This functionality allows an instantaneous waveform of up to 1 s in duration to be recorded
after the event occurs. However, continuous events are not generated when an event
occurs while continuous events are occurring. Additionally, continuous event generation
stops when measurement is stopped. Use this function when you wish to observe a wave-
form at the instant an event occurs as well as subsequent changes in the instantaneous
waveform. For the PQ3198, a waveform of up to 1 s in duration will be recorded.
HIOKI PQ3198A961-03