ENGR. REGINALDO N. MARINAY

A flow of electricity
which reaches
maximum in one
direction, decreases
to zero, then
reverses itself and
reaches maximum
in the opposite
direction.

The magnitude of a
waveform from the
peak of the positive
alternation to the
peak of the
negative
alternation.

The maximum value of a waveform of one
alternation either negative or positive
alternation.

The instantaneous value of voltage or current
is the value or current at one particular
instant.

The average value of voltage or current is
the average of the ALL the Instantaneous
value during ONE Alternation.

Effective Value of
Alternating Current
of Voltage will have
the same heating
effect on a
resistance as a
comparable value
of direct current or
voltage will have on
the same
resistance.
Ieff =
Imax
2

It is the property of an inductor to
oppose the alternating current.

The property of the capacitor to oppose
the alternating current.


The total opposition to the flow of the
alternating current.
It is the combination of resistance and
reactance.

The AC Voltage will be In-phase with
Current.


The AC voltage is
only supplying a
circuit with only an
inductor.
The voltage leads
the current by 90
degrees.


The AC voltage is
supplying a circuit
with only a
capacitor as its
load.
The current leads
the voltage by 90
degrees.

The AC voltage is
supplying the series
connection of
resistor and
inductor.

The AC voltage is
supplying the series
connection of
resistor and
capacitor.



True or Real Power
Reactive Power
Apparent Power

The power consumed by the resistive
component.

The power consumed by the reactive
component, either inductor or capacitor.

The vector sum of the true and reactive
powers.



Conductance
Susceptance
Admittance



Reciprocal of Resistance
Symbolized by capital letter “G”
G= 1/R




Reciprocal of reactance
Symbolized by “B”
Bc = 1/Xc
Bl= 1/ Xl



Reciprocal of impedance
Complex composite of conductance and
susceptance
Y = G + jB

A circuit phenomenon or condition wherein:
◦ The current is in-phase with the voltage
◦ The circuit power factor becomes unity
◦ The inductive reactance is equal to the capacitive
reactance






At
At
At
At
At
At
fr, XL = XC
fr, Z is minimum (Z=R)
fr, I is maximum (I=E/R)
fr, Z is resistive (I is in-phase with E)
f < fr, Z is capacitive
f > fr, Z is inductive





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At
At
At
At
At
At
fr, IL = IC
fr, Z is maximum (Z=RP)
fr, I is minimum (I=E/RP)
fr, Z is resistive (IT is in-phase with E)
f < fr, Z is inductive
f > fr, Z is capacitive



Quality factor
is a measure of the “goodness” or quality of a
resonant circuit
higher value for this figure of merit
corresponds to a more narrow bandwidth,
which is desirable in many applications.
Q
= X/R


The width of the resonant band of
frequencies centered around the resonant
frequency
The range of frequencies included between
the two frequencies at which the current
drops to 70 percent of its maximum value of
resonance is called the Bandwidth
BW
= FR/Q


A temporary phenomenon occurring in a
network prior to reaching a steady-state
condition.
Transient period is the period required for the
currents and voltages to adjust themselves to
the steady-state after it is switched-on.

Is the time for a change of 63.2% in the
current through inductor or the voltage
across the capacitor
T
= L/R
T= RC

Long RC Time Constant


At least five times longer than the pulse width, in time
for the applied voltage
Short RC Time Constant
◦ No more than one-fifth the pulse width, in time, for
the applied voltage