LM393 Light Sensor Readings

[Matt Pitts]

Hi There,

I have just setup the mysensors LM393 Light Sensor in the hope I can use the readings it generates to control when my house light switch on and off.

I'm a little unclear about the readings that the sensor is currently generating. I have setup exactly as described in the mysensors Light Sensor example.

Initally I only got these reading in the serial monitor, then I shone a torch into the sensor and got the higher readings, It is my understanding that the sensor should read high in the dark and low in the light? is that correct? so I don't really understand why it read higher when I shone the torch on it, can someone explain, or is something wrong with my sensor?

0
0
0
96
TSP:MSG:SEND 16-16-0-0 s=0,c=1,t=23,pt=2,l=2,sg=0,ft=0,st=ok:96
96
96
96
96
43
TSP:MSG:SEND 16-16-0-0 s=0,c=1,t=23,pt=2,l=2,sg=0,ft=0,st=ok:43
96
TSP:MSG:SEND 16-16-0-0 s=0,c=1,t=23,pt=2,l=2,sg=0,ft=0,st=ok:96
0
TSP:MSG:SEND 16-16-0-0 s=0,c=1,t=23,pt=2,l=2,sg=0,ft=0,st=ok:0

[mfalkvidd]

@Matt-Pitts the example sends a value from 0 to 100, where 0 is little light and 100 is much light.

[Matt Pitts]

@mfalkvidd so what your saying is it's working correctly?

[mfalkvidd]

@Matt-Pitts it seems so, yes.

[sincze]

@mfalkvidd , Indeed 0 - 100 not in lux as shown in Domoticz. That is why I started on a lux meter. Just to see how that works. With LM393 I just check... if value < 10 ... it must be dark enough to switch on the lights.

Works ideally when it is very dark during the day when a thunderstorm moves over your house.

[sundberg84]

@sincze - <10 is good... saves power but not approved by wife <30 for me... lights on!