Accurately Evaluate Circuits with Probes in Multisim

Multisim's Voltage, Current, Power, and Digital probes provide:

• A method for acquiring common measurements, such as voltages, branch current, and power.
• Automation of the output variable selection process in analyses (such as Transient and AC Sweep); after an analysis is run, variables from probes are automatically plotted in the Grapher.
• Annotation of important nodes on the schematic.

Probes can be found by default in a toolbar in Multisim

The available probes are:

• Voltage, Current, or Voltage and Current

These probes can measure voltage, current, or both. You can use the probe’s properties dialog to change the measurement as needed and the symbol updates to reflect the selection.

• Power

Measures the power dissipated or generated by a component.

• Digital

This probe is for interactive simulation only. During simulation, the symbol updates dynamically with 1, 0, x. High and low digital thresholds for analog nets can be set in the Digital Probe Properties dialog box.

• Differential voltage

Click once to place a voltage probe and again to place a reference probe. The voltage measured between these two points is the differential voltage.

• Reference

Provides a reference net to a voltage probe. Without a reference probe, a voltage probe will reference net 0. Use for differential voltage measurements. This an alternative to placing a pair of Differential voltage probes. Use if you have placed a number of voltage probes that you want to reference to a given point.

Note: Probes stay with wires and components when the wires are moved. They are not deleted when their nets, net segments, or components are deleted. 

Probes display measurements based on the settings in Interactive Simulation (Simulate»Analyses and simulation).

The displayed parameters can be configured locally on each probe or globally using the Probe Settings dialog box (Simulate»Probe settings).

The Digital Probe displays the instantaneous value of the digital signal directly inside of the probe symbol. It does not have a Parameters tab in its properties dialog.

The instantaneous parameters are useful for all signal types. Periodic parameters are best suited to periodic signals. They may provide misleading results for transient events. It is recommended that you use Transient analysis and the Grapher's post processing functions to perform calculations on signals that are not periodic.

When a new probe is placed, it automatically appears in the Selected variables for analysis list in the Analyses and Simulation dialog box for several of the analyses available in Multisim.

 For example:

3. Open the Transient Simulation settings by clicking on the wrench icon in the toolbar and notice the placement of the analog and digital probes in the Output tab

4. Moreover, when the analysis is run, variables from probes are automatically plotted in the Grapher and saved to a raw file . Variables from voltage, current, and power probes are plotted on the analog graph, while variables from digital probes are plotted on the digital graph.