A difference between the input thresholds that switch a signal ON and OFF, so the current switching state depends on the direction of the input change.
Also called: switching hysteresis; sensor switching hysteresis.
Why can the same input value give different switching states?
With hysteresis, switching ON and switching OFF use different thresholds. Between them, the previous state matters. An analogue input can have an ON threshold and lower reset point; some photoelectric sensors instead specify differential travel between operating and reset distances.
These are different physical quantities. Identify whether the stated gap is in distance, current, voltage or another signal level. A percentage also needs its stated reference range. Do not interpret a distance hysteresis as a length of time or assume the controller exposes an adjustable optical threshold.
No. Hysteresis separates switching levels; time-based debounce qualifies how long a state persists. They address unwanted switching through different rules and cannot be substituted for one another in a specification.
Response delay measures time after an input change; a blind zone describes ineffective spatial coverage. These mechanisms can produce similar symptoms, but the quantities and observation points differ.
Establish which signal and transition directions the hysteresis specification covers, whether the behaviour is fixed or adjustable, and the product conditions assessed. An analogue controller’s threshold scheme may differ from a counting head’s internal algorithm.
Keep the switching characteristic with product-detection evidence. Hysteresis by itself is not a percentage counting-accuracy specification and does not show that an overlapping or partly transparent product will be classified correctly.