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[[File:b2MAN_Fig212.png|thumb|left|540px720px|Running a live simulation of an Op-Amp circuit in RF.Spice A/D with Circuit Animation enabled.]]
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{{Note | Virtual instruments are not saved with the schematic, but with the project only.}}
==Virtual AmmeterVoltmeter==
Purpose: Easy measurement of current flowing through the voltages present in a partcircuit.
Procedure: Press the Setup button to expand the ammeter. First you have to indicate where you want to insert the virtual ammeter. In the General tab, first choose a part from the drop-down list of the parts in your circuit and then choose a pin on that part. The next option is the ammeter’s display range. The meter displays its measurements in two ways: text and a moving bar graph. The bar’s length expands and contracts with the current being measured, which makes it an analog readout. When the measured current exceeds the ammeter’s range, the bar changes color from blue to red. Pressing the “Auto” button overrides the fixed range and auto-adjusts the range to twice the highest current reading it sees. Under the Functionality tab, choose whether the current signal is a DC or AC one. If the signal is AC, then choose whether the RMS (Root Mean Square), Average, Absolute Average, Peak-to-Peak, or Peak values should be displayed. Then select a sample period for the ammeterWorking backwards works best here.
Behind First click the scenes, General tab to set up the ammeter instrument severs the wire connection voltmeter's nodes. Choose a node to for the selected pin positive and bridges negative nodes using the gap with a SPICE ammeterdrop down box or by using the "Probe" tool next to the drop down boxes. Note that Using the probe tool and clicking on a virtual ammeter is node that you would like to measure automatically inserted into selects that node in the [[Virtual Instruments|virtual drop down box. You should also be aware that voltmeter instruments]] panel every time are automatically inserted if you place an ammeter device a voltmeter part in your the schematic.
The next option is the voltmeter’s display range. The meter displays its voltage measurements in two ways: text and a moving bar graph. The bar’s length expands and contracts with the voltage being measured, which makes it an analog readout. When the measured voltage exceeds the voltmeter’s range, the bar changes color from its normal blue to red. Pressing the “Auto” button overrides the fixed range and auto adjusts the range to twice the highest voltage reading it sees.
The Functionality tab allows you to select whether voltage signal is a DC or AC one.
If the signal is AC, then choose whether the RMS (Root Mean Square) value should be used or the peak value. Then select the period over which the voltmeter measures.
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[[File:b2MAN_Fig32b2MAN_Fig31.png|thumb|left|360px|RF.Spice A/D Virtual AmmeterVoltmeter]]
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==Virtual Distortion MeterAmmeter==
Purpose: Easy measurement of the distortion generated within current flowing through a circuit, usually an amplifier, due to nonlinear devicespart.
Procedure: First, specify an input and an output nodePress the Setup button to expand the ammeter. The distortion meter needs an input First you have to inject a pure signal, against which it will compare indicate where you want to insert the output’s signalvirtual ammeter. SecondIn the General tab, first choose a test frequency needs to be entered (usually 1kHz for audio circuits). You can also set part from the Amplitude and offset drop-down list of the test signalparts in your circuit and then choose a pin on that part. The next option is to specify what the distortion ammeter’s display range. The meter should measuredisplays its measurements in two ways: text and a moving bar graph. A pure single-tone signal has no harmonicsThe bar’s length expands and contracts with the current being measured, as which makes it contains only one frequency, whereas an impure signal can hold many frequenciesanalog readout. When the measured current exceeds the ammeter’s range, which are usually integer multiples of the original single frequencybar changes color from blue to red. Thus a pure 1kHz signal can gives rise Pressing the “Auto” button overrides the fixed range and auto-adjusts the range to 2kHz, 3kHz, 4kHz harmonic frequenciestwice the highest current reading it sees. UsuallyUnder the Functionality tab, all choose whether the added frequencies are higher than current signal is a DC or AC one. If the input signal's fundamental frequencyis AC, but not always. Certain digital circuitsthen choose whether the RMS (Root Mean Square), for exampleAverage, can give rise Absolute Average, Peak-to sub-harmonic signalsPeak, or Peak values should be displayed. Then select a sample period for the ammeter.
The Total Harmonic Distortion (THD) figure is Behind the sum of all scenes, the harmonically related contributions ammeter instrument severs the wire connection to the signal’s magnitude. Thus, if 0.9 volts of a 1-volt output signal is made up of fundamental frequency selected pin and 0.1 volts is made up of bridges the fundamental’s second harmonic frequency, the THD equals 10%. The distortion meter can display THD of gap with a circuit or just one of the first five harmonicsSPICE ammeter. The option to display the results as Note that a percentage or in dBs virtual ammeter is quite straightforward. One percent distortion equals automatically inserted into the distortion’s contribution to the output signal being –40dB down [[Virtual Instruments|virtual instruments]] panel every time you place an ammeter device in amplitude relative to the output signal. The formula is: DB = 20Log (distortion signal / output signal) The distortion meter’s display range should be set to the maximum amount of distortion the user is willing to accept. The meter displays its measurements in two ways: text and a moving bar graph. The bar’s length expands and contracts with the distortion being measured, which makes it an analog readout. When the measured current exceeds the distortion meter’s range, the bar changes color from its normal blue to red. Pressing the “Auto” button overrides the fixed range and auto adjusts the range to twice the highest distortion reading it sees. Pressing the “Setup” button toggles the length of the Distortion Meter, so that when its setup is complete, the Distortion Meter becomes only as tall as its display bandyour schematic.
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[[File:b2MAN_Fig25b2MAN_Fig32.png|thumb|left|360px|RF.Spice A/D Virtual Distortion MeterAmmeter]]
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==Virtual Bode PlotterWattmeter==
Purpose: Easy measurement and display of power dissipation by a circuit’s frequency responsecircuit element.
Procedure: This instrument displays its measurements in Energy (power over time) is measured on a small graph. The Input/Output tab allows you to set up watt-hour meter, such as the test in regards one that connects each house to the circuitpower company’s lines. Under this tabIf we remove time from the equation, choose two inout nodes in your circuit or an input part. (Behind we end up with a power meter, as a power meter measures the scenesinstantaneous dissipation of power, much in the frequency sweep instrument adds an AC voltage source to the same way a speedometer measures a car’s instantaneous speed. The measuring of power dissipated in a purely resistive circuit, or if there is already with a DC voltage source connected to the node and groundis trivial, it takes over its settings.) You should also choose two output nodesas power equals voltage against current, P = VI. Then select The math becomes a Signal Amplitude little trickier with AC-power sources, as the waveform dictates the averaging formula used to find the power dissipated. Circuits containing reactive parts, such as capacitors and you inductors, on the other hand, are ready much more complex to run the testmeasure.
Set up Pure reactive components dissipate zero power, which makes sense in a DC circuit, as the sweep for capacitor passes no DC current and the test under the Sweep tabinductor displaces no voltage. Here you can set whether Yet, in an AC circuit, the graph’s display should reflect reactive components “seem” to dissipate power, as current passes through the capacitor and the inductor sees a logarithmic voltage drop. This counterfeit power is called “reactive power;” it is measured not in Watts, but in VARs (Volt-Amps-Reactive). In contrast, actual power is labeled “true power” or linear labeling “active power” or “real power;” it is measured in Watts. To this two powers, a third must be added, “apparent power.” Much in the same way as impedance (Z) is the combination of frequencyreactance (X) and resistance (R), apparent power is the combination of pure power with VAR. Apparent power is measured in VAs (Volt-Amps) and it’s mathematical formula symbol is “S.” Transformers are rated in VAs. Select For example, a start 100VA transformer might hold a secondary with a 10Vac winding that can sustain 10A of current output, which if attached to a 10-ohm resistor would realize 100 watts of true power (P) and stop frequency 100 VA of apparent power (S), but zero VAR of reactive power (Q). And if hooked up to a 265µF capacitor, the transformer would realize 0 watts of true power and 100 VA of apparent power and 100 VAR of reactive power. If the 10-ohm resistor and 265µF capacitor were placed in series and hooked up to the transformer’s secondary, the number transformer would realize 50 watts of steps per interval for true power and 70.7 VA of apparent power and 50 VAR of reactive power. The power triangle shown below displays the test relationships between the three powers. (Note how Pythagoras theorem nicely applies to runthe values from the previous example and how apparent power will always be equal to or greater than pure power.)
Set up Connecting the graph under power meter to a circuit can be done in two ways in the Graph Settings Circuit Setup tab: by selecting an individual part or by selecting two nodes within the circuit. Here you can The Meter Options tab control the graph's display of both the amplitude meter. The meter displays its measurements in two ways: text and the phase across the frequency sweep’s rangea moving bar graph. The Y-axis settings are the maximum bar’s length expands and minimum limits of contracts with the graphs displaypower being measured, with which makes it an analog readout. When the option to set measured current exceeds the graph display power meter’s range, the bar changes color from its normal blue to linear or in dBred. Pressing the “Auto” button overrides the fixed Y-axis tick makings range and it auto adjusts the graph’s Y-axis limits range to twice the highest current power reading it sees. The X-axis settings are the beginning and ending frequencies.
The last tab, Export, allows you to export "Measure Power As" section specifies how the graph to various formats, including graphic files, text tables, or even copy it to the Project's graph window. You can even copy the graph into memory to paste into other applicationsinstrument measures Wattage.
Press the AmplitudeReal/Phase Active - In contrast to apparent or reactive power, actual power refers to switch between the two modespower dissipation by resistive components. Press the It is labeled "Run Sweeptrue power" button to proceed with the testor "active power" or "real power", and is measured in Watts. Pressing the “Zoom” button brings up a new window with just the graph portion of the small frequency sweep instrument. Moving the cursor across the graph reveals the frequency and the dB or phase under the cursorIts mathematical formula symbol is "W".
<table><tr><td> [[File:b2MAN_Fig26Reactive - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage.png|thumb|left|360px|RFYet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q".Spice A/D Virtual Bode Plotter]]</td></tr></table>
==Virtual Function Generator==Apparent - Much in the same way as impedance (Z) is the combination of reactance (X) and resistance (R) apparent power is the combination of pure power (P) with reactive power (VAR). Apparent power is measured in VAs (Volt-Amps) and its mathematical formula symbol is "S". Transformers are rated in VAs. Purpose: Easy creation Power Factor - Power Factor (PF) or Total Power Factor (TPF) equals the ration of sinereal power (W), trianglewhich performs the actual work of creating heat, light, motion, etc., over apparent power (VA) that is the combination of real power (W) and square waves to be injected into a circuitreactive power (VAR).
Procedure: This instrument is functionally equivalent to the SPICE voltage source, but it adds easy frequency and amplitude changes. A node within the circuit must be specified to receive the function generator’s output signal. The reference node is assumed to be the ground. The DC offset of the function generator’s output can be adjusted up and down. You can choose from three waveforms: sinusoidal wave, square wave and triangle wave.
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[[File:b2MAN_Fig28b2MAN_Fig33.png|thumb|left|360px|RF.Spice A/D Virtual Function GeneratorWattmeter]]
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==Virtual Gain MeterPower Supply==
Purpose: Easy measurement To provide a quick and display of the relative strength convenient means of two (AC or DC) voltages across or inside supplying input voltage to a circuit in dBs (decibels).
Procedure: Signals often differ by great magnitudes. The miniscule output voltage from Much like an actual bench power supply, the power supply instrument provides a moving-coil phono cartridge (0.1mV) becomes amplified to 1000 volts peak-to-peak at the tube-amplifier’s selectable output tube’s plate. The ratio between these two voltage is 10,000,000. But expressed in dB (decibelss), this ratio becomes only 140 dB, a figure that is much more manageable. Aside from compressing large ranges, dBs allow fro easier math. For example, given three identical gain stages that produce a voltage gain of 31.6 times the input, placed in series, what is Both regulated and unregulated power supply types are available and the total gain? It’s time actual current delivered to find the calculator. But a ratio of 31.6 in dB circuit is 30 dB, which can directly be multiplied by 3 to yield 90 dB of gain; much easierdisplayed. AlternativelyUnlike an actual bench regulated power supply, a linear display of relative signal strength can be used by pressing the “Linear” button. The display will then show the second signal divided by the first signal. To measure the ratio between two signals in or through power supply instrument allows a circuitdegraded mode, the Gain Meter must be attached to two nodes and their references (usually, ground). The gain meter displays wherein it functions like an unregulated power supply with ripple on its measurements in two ways: text and a moving bar graph. The bar’s length expands and contracts with the ratios/gain being measuredoutput, which makes it much like an analog readout. When the measured signal gain exceeds the gain meter’s range, the bar changes color from blue to red. Pressing the “Auto” button overrides the fixed range and auto adjusts the range to twice the highest distortion reading it sees. The Functionality tab allows you to select between AC (mediated-coupled), where the meter functions as if it were coupled via a capacitor) or actual raw DC (direct coupling), where the meter reads the instantaneous voltage directly without processing. If the signal is AC, then choose whether the RMS (Root Mean Square) value, Average, Absolute Average, Peak-to-Peak, or Peak value should be usedpower supply.
The output voltage is set in voltage-selection edit box. If voltage-regulated performance is desired, then select the Regulated button for type. On the other hand, if you wish to simulate a cheap power supply, such as a wallwart, then select Unregulated for type and set the regulation to 25%, the noise to 500mV and the current to the idle current of your circuit. The regulation percentage refers to the over voltage an unregulated power supply develops when unloaded. Thus, a 10-volt/1-amp power supply with 10% regulation will putout 11 volts when it isn’t delivering any current and 10 volts when delivering its rated output current of 1A. 0% regulation means the power supply is indifferent to output current variations, as it produces a constant output voltage. The power supply noise’s frequency equals twice the wall voltage’s frequency, for example, 120 Hz, when the wall voltage is at 60 Hz. The noise’s waveform is selectable. Actual capacitor smoothed power supplies produce a triangular noise waveform; choke input power supplies, something closer to a sine wave waveform; and some switching power supplies, a square wave waveform.
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[[File:b2MAN_Fig30b2MAN_Fig29.png|thumb|left|360px|RF.Spice A/D Gain MeterPower Supply]]
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==Virtual Power SupplyFunction Generator==
Purpose: To provide a quick and convenient means Easy creation of supplying input voltage sine, triangle, and square waves to be injected into a circuit.
Procedure: Much like an actual bench power supply, the power supply This instrument provides a selectable output is functionally equivalent to the SPICE voltage(s)source, but it adds easy frequency and amplitude changes. Both regulated and unregulated power supply types are available and A node within the actual current delivered circuit must be specified to receive the circuit is displayed. Unlike an actual bench regulated power supply, the power supply instrument allows a degraded mode, wherein it functions like an unregulated power supply with ripple on its function generator’s output, much like an actual raw DC power supplysignal. The output voltage reference node is set in voltage-selection edit box. If voltage-regulated performance is desired, then select the Regulated button for type. On the other hand, if you wish assumed to simulate a cheap power supply, such as a wallwart, then select Unregulated for type and set be the regulation to 25%, the noise to 500mV and the current to the idle current of your circuitground. The regulation percentage refers to the over voltage an unregulated power supply develops when unloaded. Thus, a 10-volt/1-amp power supply with 10% regulation will putout 11 volts when it isn’t delivering any current and 10 volts when delivering its rated output current DC offset of 1A. 0% regulation means the power supply is indifferent to function generator’s output current variations, as it produces a constant output voltagecan be adjusted up and down. The power supply noise’s frequency equals twice the wall voltage’s frequencyYou can choose from three waveforms: sinusoidal wave, for example, 120 Hz, when the wall voltage is at 60 Hz. The noise’s waveform is selectable. Actual capacitor smoothed power supplies produce a triangular noise waveform; choke input power supplies, something closer to a sine square wave waveform; and some switching power supplies, a square triangle wave waveform.
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[[File:b2MAN_Fig29b2MAN_Fig28.png|thumb|left|360px|RF.Spice A/D Power SupplyVirtual Function Generator]]
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==Virtual Transient Signal RecorderGain Meter==
Purpose: To record up to two signals for either a predetermined period Easy measurement and display of time or the entire length relative strength of the simulation run and save the data to two (AC or DC) voltages across or inside a filecircuit in dBs (decibels).
Setting up Procedure: Signals often differ by great magnitudes. The miniscule output voltage from a moving-coil phono cartridge (0.1mV) becomes amplified to 1000 volts peak-to-peak at the Transient Recorder tube-amplifier’s output tube’s plate. The ratio between these two voltage is as simple as specifying the Trace node10,000,000. But expressed in dB (sdecibels) and reference node(s) and then setting up , this ratio becomes only 140 dB, a figure that is much more manageable. Aside from compressing large ranges, dBs allow fro easier math. For example, given three identical gain stages that produce a voltage gain of 31.6 times the capture windowinput, placed in series, what is the total gain? It’s time to find the calculator. But a ratio of 31.6 in dB is 30 dB, which can directly be multiplied by 3 to yield 90 dB of gain; much easier.
The Traces tab is where you set up the Alternatively, a linear display of relative signal(s) to recordstrength can be used by pressing the “Linear” button. The Traces tab has separate sub-tabs that allow you to set up Trace 1 and Trace 2display will then show the second signal divided by the first signal.
For each traceTo measure the ratio between two signals in or through a circuit, make sure that the Show Trace box is checked. By default, Trace 1 is always showing, but if you wish Gain Meter must be attached to display Trace 2two nodes and their references (usually, you need to check the boxground). Select an input node The gain meter displays its measurements in two ways: text and Reference node using a moving bar graph. The bar’s length expands and contracts with the drop down box or using the probe tool v5picsratios/probe.pnggain being measured, which will allow you to "sample" a node in makes it an analog readout. When the circuit and have that node number automatically entered into measured signal gain exceeds the respective field. If the circuit's node numbers are not showinggain meter’s range, you can display them by clicking on the Show Node Names v5pics/show_nodebar changes color from blue to red.png Pressing the “Auto” button in overrides the toolbar. Additionally, you can select the Gain fixed range and Vertical Offset and Width of auto adjusts the trace can be set here. Keep in mind that wider widths can slow down range to twice the drawing of the signal and simulationhighest distortion reading it sees.
The Preset Functionality tab sets up allows you to select between AC (mediated-coupled), where the Recorder's capture and display propertiesmeter functions as if it were coupled via a capacitor) or DC (direct coupling), where the meter reads the instantaneous voltage directly without processing. If the signal is AC, then choose whether the RMS (Root Mean Square) value, Average, Absolute Average, Peak-to-Peak, or Peak value should be used.
The most important thing to understand is the difference between the Data Capture Interval and Interactive Viewing Interval<table><tr><td> [[File:b2MAN_Fig30. The Data Capture Interval specifies what length of data to save. The Interactive Viewing Interval specifies what the instrument window displayspng|thumb|left|360px|RF.Spice A/D Gain Meter]]</td></tr></table>
The Data Capture's All setting captures and saves the data for the entire length ==Virtual Distortion Meter== Purpose: Easy measurement of the simulation run until you stop the simulation. The Most Recent button activates the Duration box and allows you to specify distortion generated within a certain period of data to save. If you specify the most recent 5 seconds to capturecircuit, and the simulation runs for 23 secondsusually an amplifier, only the data from seconds 18-23 are captured. Everything else is discarded. The Fixed button activates both the Start and Duration boxes and allows you due to specify that a certain time interval's data is kept. If you specify a start of 1 second and a duration of 5 seconds, then only the data from seconds 1 to 6 are kept. Note that the Duration is not the same as a stop time. It specifies the LENGTH of time, not a fixed timenonlinear devices.
Procedure: First, specify an input and an output node. The View settings distortion meter needs an input to inject a pure signal, against which it will compare the output’s signal. Second, a test frequency needs to be entered (usually 1kHz for audio circuits). You can also set the Amplitude and offset of the test signal. The next option is to specify what data the distortion meter should measure. A pure single-tone signal has no harmonics, as it contains only one frequency, whereas an impure signal can hold many frequencies, which are usually integer multiples of the original single frequency. Thus a pure 1kHz signal can gives rise to display in 2kHz, 3kHz, 4kHz harmonic frequencies. Usually, all the graph windowadded frequencies are higher than the input signal's fundamental frequency, but not always. Certain digital circuits, for example, can give rise to sub-harmonic signals.
Again, The Total Harmonic Distortion (THD) figure is the Interactive Viewing settings are independent sum of all the Data Capture settingsharmonically related contributions to the signal’s magnitude. The All, Most RecentThus, if 0.9 volts of a 1-volt output signal is made up of fundamental frequency and Fixed boxes function like 0.1 volts is made up of the Data Captures settingsfundamental’s second harmonic frequency, but this only affects the graph displayTHD equals 10%. Note that even data that is not displayed in the graph The distortion meter can be retained for saving to display THD of a filecircuit or just one of the first five harmonics. If The option to display the results as a Most Recent viewing interval of 50ms percentage or in dBs is specified and quite straightforward. One percent distortion equals the Data Capture setting distortion’s contribution to the output signal being –40dB down in amplitude relative to the output signal. The formula is : DB = 20Log (distortion signal / output signal) The distortion meter’s display range should be set to All, then only the most recent 50ms maximum amount of data is shown, but ALL distortion the data user is being stored willing to accept. The meter displays its measurements in memory two ways: text and can be saved to a filemoving bar graph. The bar’s length expands and contracts with the distortion being measured, which makes it an analog readout. When the measured current exceeds the distortion meter’s range, the bar changes color from its normal blue to red. Pressing the “Auto” button overrides the fixed range and auto adjusts the range to twice the highest distortion reading it sees. Pressing the “Setup” button toggles the length of the Distortion Meter, so that when its setup is complete, the Distortion Meter becomes only as tall as its display band.
The Export tab allows you to save the data (specified by the Data Capture Interval setting) to either the clipboard to be pasted into another program or saved directly to a file.
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[[File:b2MAN_Fig27b2MAN_Fig25.png|thumb|left|360px|RF.Spice A/D Virtual Transient Signal RecorderDistortion Meter]]
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==Virtual VoltmeterBode Plotter==
Purpose: Easy measurement of the voltages present in a circuitcircuit’s frequency response.
Procedure: Working backwards works best hereThis instrument displays its measurements in a small graph. The Input/Output tab allows you to set up the test in regards to the circuit. Under this tab, choose two inout nodes in your circuit or an input part. (Behind the scenes, the frequency sweep instrument adds an AC voltage source to the circuit, or if there is already a voltage source connected to the node and ground, it takes over its settings.) You should also choose two output nodes. Then select a Signal Amplitude and you are ready to run the test.
First click the General tab to set Set up the voltmeter's nodes. Choose a node to sweep for the positive and negative nodes using test under the drop down box or by using the "Probe" tool next to the drop down boxesSweep tab. Using the probe tool and clicking on a node that Here you would like to measure automatically selects that node in can set whether the drop down box. You graph’s display should also be aware that voltmeter instruments are automatically inserted if you place reflect a voltmeter part in logarithmic or linear labeling of frequency. Select a start and stop frequency and the schematicnumber of steps per interval for the test to run.
The next option is Set up the voltmeter’s display range. The meter displays its voltage measurements in two ways: text and a moving bar graphunder the Graph Settings tab. The bar’s length expands Here you can control the graph's display of both the amplitude and contracts with the voltage being measured, which makes it an analog readoutphase across the frequency sweep’s range. When The Y-axis settings are the measured voltage exceeds maximum and minimum limits of the voltmeter’s rangegraphs display, with the bar changes color from its normal blue option to redset the graph display to linear or in dB. Pressing the “Auto” button overrides the fixed range Y-axis tick makings and it auto adjusts the range graph’s Y-axis limits to twice the highest voltage current reading it sees. The X-axis settings are the beginning and ending frequencies.
The Functionality last tab , Export, allows you to select whether voltage signal is export the graph to various formats, including graphic files, text tables, or even copy it to the Project's graph window. You can even copy the graph into memory to paste into other applications. Press the Amplitude/Phase to switch between the two modes. Press the "Run Sweep" button to proceed with the test. Pressing the “Zoom” button brings up a DC new window with just the graph portion of the small frequency sweep instrument. Moving the cursor across the graph reveals the frequency and the dB or AC onephase under the cursor.
If the signal is AC, then choose whether the RMS (Root Mean Square) value should be used or the peak value. Then select the period over which the voltmeter measures.
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[[File:b2MAN_Fig31b2MAN_Fig26.png|thumb|left|360px|RF.Spice A/D Virtual VoltmeterBode Plotter]]
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==Virtual WattmeterTransient Signal Recorder==
Purpose: Easy measurement and display To record up to two signals for either a predetermined period of power dissipation by time or the entire length of the simulation run and save the data to a circuit elementfile.
Energy (power over time) is measured on a watt-hour meter, such as the one that connects each house to the power company’s lines. If we remove time from the equation, we end Setting up with a power meter, as a power meter measures the instantaneous dissipation of power, much in the same way a speedometer measures a car’s instantaneous speed. The measuring of power dissipated in a purely resistive circuit with a DC voltage source Transient Recorder is trivial, as power equals voltage against current, P = VI. The math becomes a little trickier with AC-power sources, simple as specifying the waveform dictates the averaging formula used to find the power dissipated. Circuits containing reactive parts, such as capacitors Trace node(s) and inductors, on reference node(s) and then setting up the other hand, are much more complex to measurecapture window.
Pure reactive components dissipate zero power, which makes sense in a DC circuit, as the capacitor passes no DC current and the inductor displaces no voltage. Yet, in an AC circuit, the reactive components “seem” to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power The Traces tab is called “reactive power;” it is measured not in Watts, but in VARs (Volt-Amps-Reactive). In contrast, actual power is labeled “true power” or “active power” or “real power;” it is measured in Watts. To this two powers, a third must be added, “apparent power.” Much in where you set up the same way as impedance signal(Zs) is the combination of reactance (X) and resistance (R), apparent power is the combination of pure power with VARto record. Apparent power is measured in VAs (VoltThe Traces tab has separate sub-Amps) and it’s mathematical formula symbol is “S.” Transformers are rated in VAs. For example, a 100VA transformer might hold a secondary with a 10Vac winding tabs that can sustain 10A of current output, which if attached allow you to a 10-ohm resistor would realize 100 watts of true power (P) and 100 VA of apparent power (S), but zero VAR of reactive power (Q). And if hooked set up to a 265µF capacitor, the transformer would realize 0 watts of true power Trace 1 and 100 VA of apparent power and 100 VAR of reactive powerTrace 2. If the 10-ohm resistor and 265µF capacitor were placed in series and hooked up to the transformer’s secondary, the transformer would realize 50 watts of true power and 70.7 VA of apparent power and 50 VAR of reactive power. The power triangle shown below displays the relationships between the three powers. (Note how Pythagoras theorem nicely applies to the values from the previous example and how apparent power will always be equal to or greater than pure power.)
For each trace, make sure that the Show Trace box is checked. By default, Trace 1 is always showing, but if you wish to display Trace 2, you need to check the box. Select an input node and Reference node using the drop down box or using the probe tool v5pics/probe.png, which will allow you to "sample" a node in the circuit and have that node number automatically entered into the respective field. If the circuit's node numbers are not showing, you can display them by clicking on the Show Node Names v5pics/show_node.png button in the toolbar. Additionally, you can select the Gain and Vertical Offset and Width of the trace can be set here. Keep in mind that wider widths can slow down the drawing of the signal and simulation.
Connecting the power meter to a circuit can be done in two ways in the Circuit Setup tab: by selecting an individual part or by selecting two nodes within the circuit. The Meter Options Preset tab control sets up the Recorder's capture and display of the meter. The meter displays its measurements in two ways: text and a moving bar graph. The bar’s length expands and contracts with the power being measured, which makes it an analog readout. When the measured current exceeds the power meter’s range, the bar changes color from its normal blue to red. Pressing the “Auto” button overrides the fixed range and auto adjusts the range to twice the highest power reading it seesproperties.
The "Measure Power As" section most important thing to understand is the difference between the Data Capture Interval and Interactive Viewing Interval. The Data Capture Interval specifies what length of data to save. The Interactive Viewing Interval specifies how what the instrument measures Wattagewindow displays.
Real/Active - In contrast The Data Capture's All setting captures and saves the data for the entire length of the simulation run until you stop the simulation. The Most Recent button activates the Duration box and allows you to apparent or reactive power, actual power refers specify a certain period of data to save. If you specify the power dissipation by resistive componentsmost recent 5 seconds to capture, and the simulation runs for 23 seconds, only the data from seconds 18-23 are captured. It Everything else is labeled "true power" or "active power" or "real power", discarded. The Fixed button activates both the Start and Duration boxes and allows you to specify that a certain time interval's data is measured in Wattskept. Its mathematical formula symbol If you specify a start of 1 second and a duration of 5 seconds, then only the data from seconds 1 to 6 are kept. Note that the Duration is "W"not the same as a stop time. It specifies the LENGTH of time, not a fixed time.
Reactive - Pure reactive components dissipate zero power, which makes sense The View settings specify what data to display in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q"graph window.
Apparent - Much in the same way as impedance (Z) is Again, the combination Interactive Viewing settings are independent of reactance (X) the Data Capture settings. The All, Most Recent, and resistance (R) apparent power is Fixed boxes function like the combination of pure power (P) with reactive power (VAR)Data Captures settings, but this only affects the graph display. Apparent power Note that even data that is measured not displayed in VAs (Volt-Amps) and its mathematical formula symbol is "S". Transformers are rated in VAsthe graph can be retained for saving to a file. Power Factor - Power Factor (PF) or Total Power Factor (TPF) equals the ration If a Most Recent viewing interval of real power (W)50ms is specified and the Data Capture setting is set to All, which performs then only the actual work most recent 50ms of creating heat, light, motion, etc., over apparent power (VA) that data is shown, but ALL the combination of real power (W) data is being stored in memory and reactive power (VAR)can be saved to a file.
The Export tab allows you to save the data (specified by the Data Capture Interval setting) to either the clipboard to be pasted into another program or saved directly to a file.
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[[File:b2MAN_Fig33b2MAN_Fig27.png|thumb|left|360px|RF.Spice A/D Virtual WattmeterTransient Signal Recorder]]
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