| functional unit that generates an output variable the value of which depends on the sign of the value of its input variable according to the formula|
|t||is the time;|
|u(t)||is the input variable;|
|v(t)||is the output variable.|
|V1||is a constant value of the output variable.|
Note 1 to entry: This entry was numbered 351-32-23 in IEC 60050-351:2006.