What is VA?
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I have A transformer That has two 16V, 35VA rating. I do not know
what is " VA "? I don't think it means AMPS, this transformer is not
that big in size.
Thanks
what is " VA "? I don't think it means AMPS, this transformer is not
that big in size.
Thanks
Comments
> I have A transformer That has two 16V, 35VA rating. I do not know
> what is " VA "? I don't think it means AMPS, this transformer is
not
> that big in size.
>
> Thanks
VA stands for Volt-Amps. In pure DC, volts times amps = power
(watts). VA is approximately the same thing, but in a transformer,
the voltage is not always in phase with the current, so this may not
quite equal the true power output of the transformer. If your circuit
draws two amps at 16 Volts AC, that is 32 VA, but is
only 'approximately' 32 watts.
Chuck
>I have A transformer That has two 16V, 35VA rating. I do not know
>what is " VA "? I don't think it means AMPS, this transformer is not
>that big in size.
It basically means watts. VA = Volts times Amps.
For the additional gory detail, do a search on "power factor" and "watts"
together.
Jim H
amps equals watts.
On 12 Nov 2001, at 20:34, iamturbo2000@y... wrote:
> I have A transformer That has two 16V, 35VA rating. I do not know what
> is " VA "? I don't think it means AMPS, this transformer is not that
> big in size.
>
> Thanks
>
>
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rated at about 2 amps.
Original Message
> I have A transformer That has two 16V, 35VA rating. I do not know
> what is " VA "? I don't think it means AMPS, this transformer is not
> that big in size.
VA as often called is a product of Volts and Amperes and by
definition is reactive power.
the true power is the VA product times the cosine of the phase
displacement in radians between the voltage and current.
Albert Catano
--- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> VA is volt-amperes. Take the 35 VA and divide it by 16 -- the
transformer is
> rated at about 2 amps.
>
>
Original Message
>
> > I have A transformer That has two 16V, 35VA rating. I do not know
> > what is " VA "? I don't think it means AMPS, this transformer is
not
> > that big in size.
we are talking about relations between pure sine waves.
Under resistive loads, the phase angle is zero and the VA product is
True power.
The pase angle in radians is normally called Power Factor (P.F.)
If the waveforms are non sinosoidal (distorted) the waveform consist
of a series of harmonics better known as Fourier Series.
--- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> VA is volt-amperes. Take the 35 VA and divide it by 16 -- the
transformer is
> rated at about 2 amps.
>
>
Original Message
>
> > I have A transformer That has two 16V, 35VA rating. I do not know
> > what is " VA "? I don't think it means AMPS, this transformer is
not
> > that big in size.
pure sine waves.
Apparent power is VA (Volts*Amperes)
The Reactive power is always greater than the True power.
Power Factor PF= cos(theta)
For normal power utilities, the PF is about 0.80
If the load is inductive such as electric motors, the phase
relationship between Voltage and Current LAGS (PF less than 0.8)
If the load is capacitive such as capacitors, the phase relationship
between Voltage and Current LEADS (PF more than 0.80)
To add to the confusion, the rated Volts and Amperes are the RMS
(RootMeanSquare) values of the sinosoid or 0.707 of the peak value
for a pure sinosoid.
--- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> So let's see here? Power Factor is the relationship between true
power
> and apparent power? True power = E*I and Apparent power equals
What?
> and power factor equals ?
>
> I pose these questiojns for the newbies in the group.
>
> Leroy
>
> acatano2002@y... wrote:
> >
> > That is wrong.
> > VA as often called is a product of Volts and Amperes and by
> > definition is reactive power.
> > the true power is the VA product times the cosine of the phase
> > displacement in radians between the voltage and current.
> >
> > Albert Catano
> >
> >
> > --- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> > > VA is volt-amperes. Take the 35 VA and divide it by 16 -- the
> > transformer is
> > > rated at about 2 amps.
> > >
> > >
Original Message
> > >
> > > > I have A transformer That has two 16V, 35VA rating. I do not
know
> > > > what is " VA "? I don't think it means AMPS, this transformer
is
> > not
> > > > that big in size.
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@y...
> > from the same email address that you subscribed. Text in the
Subject and Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
transformer? And we wonder why people think electronics are impossible to
understand.
Roger Kadau
> True power s P=VA*cos(theta) is true only for resistive loads and pure
sine waves.
> Apparent power is VA (Volts*Amperes)
> The Reactive power is always greater than the True power.
> Power Factor PF= cos(theta)
> For normal power utilities, the PF is about 0.80
> If the load is inductive such as electric motors, the phase relationship
between Voltage and Current LAGS (PF less than 0.8)
> If the load is capacitive such as capacitors, the phase relationship
between Voltage and Current LEADS (PF more than 0.80)
> To add to the confusion, the rated Volts and Amperes are the RMS
> (RootMeanSquare) values of the sinosoid or 0.707 of the peak value for a
pure sinosoid.
and apparent power? True power = E*I and Apparent power equals What?
and power factor equals ?
I pose these questiojns for the newbies in the group.
Leroy
acatano2002@y... wrote:
>
> That is wrong.
> VA as often called is a product of Volts and Amperes and by
> definition is reactive power.
> the true power is the VA product times the cosine of the phase
> displacement in radians between the voltage and current.
>
> Albert Catano
>
>
> --- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> > VA is volt-amperes. Take the 35 VA and divide it by 16 -- the
> transformer is
> > rated at about 2 amps.
> >
> >
Original Message
> >
> > > I have A transformer That has two 16V, 35VA rating. I do not know
> > > what is " VA "? I don't think it means AMPS, this transformer is
> not
> > > that big in size.
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and Body
of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
explain all this in more detail. I have taught the classes and I think
it's mostly a bunch of BS! In the real world you can assume that VA =
Watts. It doesn't but for all PRACTICAL purposes it's real close. This
theory works pretty much at home, just don't apply it to a Service grid
at your local company.
Regards,
Leroy
Roger Kadau wrote:
>
> Goodness gracious, I need this to go down to Radio Shack and pick up a
> transformer? And we wonder why people think electronics are impossible to
> understand.
>
> Roger Kadau
>
> > True power s P=VA*cos(theta) is true only for resistive loads and pure
> sine waves.
> > Apparent power is VA (Volts*Amperes)
> > The Reactive power is always greater than the True power.
> > Power Factor PF= cos(theta)
> > For normal power utilities, the PF is about 0.80
> > If the load is inductive such as electric motors, the phase relationship
> between Voltage and Current LAGS (PF less than 0.8)
> > If the load is capacitive such as capacitors, the phase relationship
> between Voltage and Current LEADS (PF more than 0.80)
> > To add to the confusion, the rated Volts and Amperes are the RMS
> > (RootMeanSquare) values of the sinosoid or 0.707 of the peak value for a
> pure sinosoid.
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and Body
of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
circuit of say a large motor which has a high inductive load? Let's be
clear here for all who have an interest..
Leroy
acatano2002@y... wrote:
>
> True power s P=VA*cos(theta) is true only for resistive loads and
> pure sine waves.
> Apparent power is VA (Volts*Amperes)
> The Reactive power is always greater than the True power.
> Power Factor PF= cos(theta)
> For normal power utilities, the PF is about 0.80
> If the load is inductive such as electric motors, the phase
> relationship between Voltage and Current LAGS (PF less than 0.8)
> If the load is capacitive such as capacitors, the phase relationship
> between Voltage and Current LEADS (PF more than 0.80)
> To add to the confusion, the rated Volts and Amperes are the RMS
> (RootMeanSquare) values of the sinosoid or 0.707 of the peak value
> for a pure sinosoid.