Zero crossing

As a zero crossing, (Engl. Zero Crossing ), a zero point with sign change , respectively.

In the case of periodic processes (e.g. sine , square , triangle , sawtooth voltage without superimposed DC voltage), a constant, even number of zero crossings per period can be specified.

Zero crossing of a sine; here in engl. as zero crossing referred

A sinusoidal voltage has two zero crossings per period:

• at the time (for example at the time ) ${\displaystyle \!\,t_{1}=t}$ ${\displaystyle t=0}$
• after half a period, at (with f = frequency of the signal) ${\displaystyle t_{2}=t+{\frac {1}{2\cdot f}}}$

After a complete period, at a zero crossing then takes place, which is to be assigned to the next period. ${\displaystyle t_{3}=t+{\frac {1}{f}}}$

The zero crossing of a signal is important in electronic measurement technology as a trigger or in circuit technology when switching capacitive loads. In the demodulation of frequency shift of the zero-crossing can be used as a simple, error-prone process.

literature

• Gert Hagmann: Fundamentals of electrical engineering . 6th edition. AULA-Verlag GmbH, Wiesbaden 1997, ISBN 3-89104-614-6 .

See also

• Zero crossing switch