The function "dark-switching" means that the concerning output is switched (guides power) when no light strikes the receiver: this is the function normally closed (NC). The switching output of a photoelectric device is active (for example responded output relais) when no light strikes the light receiver. If the light receiver is unlighted when dark-switched, the succeeding amplifier is switched and the output relais is responding. When the light receiver is lighted, the relais is decreasing.
DC light is light with a basically constant effective radiated power (for example electric light bulbs). The advantage is a relatively high light intensity but the disadvantage is the slow performance which excludes the modulation or pulsation of the light.
The DC light operation is the operation of a light barrier or light sensor where the DC light part of the luminous flux is analysed within the light receiver.
The degree of protection specifies the suitability of electric devices for certain environmental characteristics in regard to EN 60529 (IEC 60529). Furthermore, it indicates the protection of humans against a potential risk in using it. The degree of protection IP is followed by two key numbers which define 1) the scope of protection against contact and 2) the scope of protection against penetration of humidity. A complete overview about the classification of degrees of protection is shown under "protection classes" in this dictionary.
The time between switching on the operating voltage and the start of the operational readiness of the proximity switch is called "delay before start-up". In accordance with DIN EN 6947-5-2, this time should not exceed 300 ms.
Diffuse reflectance is the undirected reflection of radiation at non-reflective surfaces.
The most common switch of a proximity sensor is the digital output. Determined by the approximation of the measuring object to the active surface, a change of the alternating field or a corresponding reflection will be generated. The change of the oscillation amplitude that is connected with it, will be transformed in sensor electronic over an electronic trigger at a defined point of the change into a digital ON or OFF signal. In doing so, there is a change of status HIGH into status LOW or the other way round. This status change is usually signalised by a LED display.
After the transmitter light leaves the sensor, it diverges in a certain aperture angle.
Sensors with dynamic output are switching the output signal as pulse - only for the length of the real duration in which the object is situated inside the area of the alternating field. This function guarantees a considerably higher sensitivity of the sensors than standard devices do. For very fast movements, the pulse can only remain for a few milliseconds. Because of this, Pulsotronic offers sensors with dynamic output behaviour and an additional pulse extension. This guarantees the secure switching of the succeeding control unit.
Extraneous light is the light that strikes the measuring point of the photo-electric device or that comes from an external source additionally to the light transmitter.