Opto Modules and Solid-State Relays - Weidmüller - #4

0:;!;;co..:jlci a;; t:-is::;ti ..-i::

circuits by means of a control circuit. On the one hand this allows applications with fforc-nt porfci 'nance ratings to be operated ay relatively low switching CLirrerts. And on the other electrical isolation ') between control and load circuits is provided to assure protection of components should a malfunction occur.

In contrast to electromechanical relays optocouplers do not have any mechanical parts that ore p'coe to wear. To enable the switchin;-; oceratio" o 'o-it 5l3n.nl triojp.erso via on LCD the control circuit that causes a light-sensitive semiconductor receiver to complete a connected load circuit. Transmitter (LED) and toco vet :'foi example a phototransis-tor) are embedded in a light conducting plastic material and encased in a light-proof casuy Liai p-otects against outside influences.

Two design types are differentiated:

Face-to-face design with LED and transistor mounted across from each other with direct light contact Coplanar design with LED and transistor on the same level. In this case Lie bsri™ of giv. is transferred by reflection according to the principle of riors-optics.

The voltage, which can be applied to the opto output itself, is restricted by the sens:", vr.y of vie semiconductor receiver ^phototransistor). Ir apiilicaticrc in which only low currents or voltages are required in the load circii t I is possible to use the component without an additional auxiliary circuit in an opto

ndaptaiions to accommodate the different performance levels of the phototransistor and the load circuit (switching amplification). Modules other than optos equipped with a switching amplifiei

are called solid-state relays (SSFfl. Ci*kc