Photo Sensorer on intelligent house control system (IHC)

Thread Starter


Joined Aug 1, 2013
Hello everyone,

I have gotton my hands on some of these photo sensors:
SICK WS/WE100L-F1131

I supply the sensor with 24v and I can messure that when I break the beam, 24V comes out of the sensor line.

Now the thing is, I need to feed this sensor output to an input module on my IHC system, but the way triggering works on this is:

On an input port, a pull-up resistor keeps the input at 24V, then when you connect GND to the port, it registers the port as being active, it does the when the line between GND and input port is < 300Ω

I need some help to build a diagram for this, does anyone have a suggestion for this?


Joined Sep 9, 2010
Since you have plenty of voltage on the input signal, a MOSFET would be another option for the transistor. If you have multiple sensors, you might consider a transistor or MOSFET array - multiple transistors in one package. See ULN2003AN.