Multisim Live import: what converts and what does not
The conversion is good but not complete. Here is what comes across, what turns into a placeholder, and what to check before you trust a result.
Britt Espinosa
Last Update il y a un mois
The dialog says it plainly: importing Multisim Live circuits is experimental, and imported schematics and results are worth validating before you rely on them. This article is the detail behind that sentence.
What comes across
- Components that CircuitSim has a mapping for, with their designator, value, and parameters
- Wires, redrawn on CircuitSim's grid
- Designator and value labels, with their size, weight, and rotation
- Probes, including current, voltage, and digital probes
- Net labels
- Text annotations, as comments on the schematic
- Simulation settings, from a .msjs: the analysis type, transient start and stop and step, AC sweep range and points, and the shunt resistance
A .ms14 carries less than a .msjs. It has no saved simulation settings, and probe colors are assigned from a fixed rotation rather than read from the file, so the trace colors will not match your original. Prefer the .msjs when you have both.
Components with no mapping become placeholders
CircuitSim matches each part against a library of roughly four thousand mappings. A part with no match is not dropped. It is turned into a placeholder so the shape of the circuit survives, and you will see:
- A plain rectangle with pin stubs where the part used to be, not its original symbol
- A new custom component in your library named [MSL placeholder] followed by the part's designator and value
- The original parameters carried on it as free text fields
A placeholder holds the right pins in the right places, so the wiring stays intact. What it may not have is a working model. If the source file did not carry a usable SPICE template, the placeholder contributes nothing to the simulation and results through that part of the circuit will be wrong. Replace placeholders with real components before you trust a run.
Placeholders are saved into your custom components, so a large import can fill that library with [MSL placeholder] entries. Importing the same part again reuses the placeholder rather than making another one.
Where the import warnings go
The importer records a warning for every placeholder it makes. It does not show them to you during the import. Instead:
- The circuit's description reads Imported circuit. 6 import warning(s) were generated.
- A note titled Import warnings is added to the circuit, listing each one
The Notes panel is closed when an imported circuit first opens, so open it and read that note. It is the fastest way to see which parts did not map.
Wiring is rebuilt, not copied
Connectivity is worked out from the geometry rather than carried over as a net list. Everything is snapped to CircuitSim's grid, and diagonal wires are redrawn as right angles. For a tidy, grid-aligned Multisim Live schematic this comes out right.
Where an endpoint cannot be matched to a pin, the importer leaves a small free-standing stub node so the wire is still visible. Nothing warns you when this happens. That is the failure worth looking for: a wire that appears to touch a pin but is attached to a stub instead. Click a wire and drag a component a little to see what moves with it.
What does not come across at all
- Instruments. The oscilloscope, multimeter, function generator, and the rest are not imported. Use CircuitSim's probes and charts instead.
- Saved waveforms and measurements. Only the circuit comes across, not results you had already run.
- Analyses other than transient, AC sweep, DC operating point, and DC sweep. Anything else falls back to the CircuitSim default.
- Second and later sheets. Only the first sheet of a design is read.
- Subcircuits and hierarchical blocks. These have no equivalent in the importer and end up as placeholders or are not seen.
- Sheet graphics. Boxes, arrows, images, logos, and title blocks are dropped. Text annotations do survive.
- Anything hidden. Hidden components, wires, labels, and text are all filtered out.
Values are copied as text
Values come across as the text that was on the schematic, with the unit removed and the SI prefix left in place. Nothing checks that the result is a number the simulator will accept. Spot-check the values on any part you care about, especially anything that was written unusually.
A review order that finds problems fast
- Open the Notes panel and read Import warnings to see which parts became placeholders.
- Check that the circuit has a ground.
- Look for stub nodes where a wire should meet a pin.
- Check the values on the parts that set the operating point.
- Open the simulation settings and confirm the analysis and its range.
- Run it, and compare against what the circuit did in Multisim Live.
If a circuit will not run after an import, the troubleshooting articles for no ground, floating nodes, and something not connected cover the three causes that come up most.
Still stuck?
CircuitSim is built by a small team and we are happy to help. Email [email protected] and tell us what you were doing and the name of the circuit or group involved. If you are talking to the chat assistant, leave your email address in the chat and one of us will reply.