On the Characteristic page of the Open Component dialog box you specify input characteristic
for non-linear components. You specify pais of data in a standard string grid. Add a new point after the cursor position by clicking on Add. Delete the marked point by clicking on Delete. You can manipulate the order of the points by the Sort button (the first column is used for sorting, starting with the lowest number) or the up/down arrows marked with Move. The user can edit the points directly any time.
The MOV components contain an internal routine (similar to ATP's ZNO FITTER) to convert the U/I points into exponential segments (i=a*(U/U0)^q).
The Saturable transformer components contain routines (similar to SATURA) to convert RMS U/I points into peak fluxlinkage/current points.
Is is possible the export the characteristic to an external file or to the Windows clipboard as text. The whole characterisitic is copied (no marking is supported or required). You can also paste a characteristic from the clipboard. It is thus possible to bring an old ATP file up in a text editor and mark a characteristic (the flag 9999 is optional) and copy it to the clipboard and paste it into the characterisitic page. The number of point with automatically be adjusted (the pasted characterisitic could be truncated to ensure that the number of data is less or equal to 64) so you do not have to click on Add or Delete before pasting. ATPDraw uses fixed format 16 character columns to separate the numbers. Pasting in from a text file with 'C' in the first column gives a wrong result.
The File section at the bottom of the page contains a section where you can add an "external" characteristic. Click on the Edit button to modify the extrernal characteristic. The Data source field is just a reminder of where the file with the characteristic was stored. It is also possible to just type in the characteristic without specifying any file at all, and in this case the Data source field will be empty. The "external" characteristic is stored in memory and written directly to the final ATP- file (without using $Include). There is no (practical) limit on how large the external characteristic can be. Both internal and external characteristics can be stored, and the external is used when the Include characteristic button is checked.
You can get a graph of the internal characteristic by clicking View. The internal characteristic can be save to disk by clicking Save.