Electrical – LTSpice component attribute editor problem

The command "test.asc -run -b" does not run LTSpice, it simply opens the file "test.asc". It only opens in LTSpice because the file association for ".asc" is assigned to LTSpice in the operating system (if it was assigned to eg. notepad then it would open in that program instead). The ".asc" filetype is set up to only pass the file name to LTSpice, not the whole command line.

Your command should start with the name of the executable you want to run ie. "scad3.exe", followed by any parameters you want to give it ie. "test.asc -run -b". LTSpice will then be able to read the full command line, run the simulation and produce the expected output files ("test.log", "test.net").

If you read in the LTspice manual, you'll see that it says it's breakdown voltage is set by the voltage applied at its control terminals. The voltage can be of any sign, any polarity (it counts as abs(V(ctl))), and the calculation is like this: if your applied voltage is 10V, the series resistance is 1 Ohm, Rclamp=1 and the control voltage is 1V (I presume), then the varistor will breakdown at 1V (the controlling voltage), meaning from the total of 10V you'll have 10-1=9V which, divided by the total resistance of 3 Ohms results in 3A. If your source voltage is 7V, series resistance is 2 Ohms, Rclamp=1.5 and controlling voltage 3V => (7-3)/(2.5+1.5)=4/4=1A.