tlim=100×
-3
10
;​​v[t_]:=
0.15
0⩽t⩽50
-3
10
-0.3
50
-3
10
⩽t⩽60
-3
10
0
t>60
-3
10
​​Plot[Quantity[v[t],"Volts"],{t,0,tlim},Frame->True,FrameLabel->{{Automatic,None},{None,None}},PlotRangeAll]​​Plot[UnitSimplify[Quantity[v[t]],"Volts"],{t,Quantity[0,"Seconds"],Quantity[tlim,"Seconds"]},GridLinesAutomatic,Frame->True,AxesLabel->Automatic]