LIGHT SENSOR

or

LIGHT SENSOR-L

Component Side	Light Side Side	Side View w/optional socket

Features:

• Size  (1.0 x 1.0 inches)
• Simple 3-wire connections or optional 3-pin connector
• No External Power Supply required (powered by the BrightSign)
• 4-corner mounting holes for mounting (.7 X .7 centers)
• LED 'Trip' Indicator on board
• Potentiometer for adjusting the 'Trip' level

This 'Ambient Light Sensor' is designed to trip when the light amount is interrupted or increased.  The trip level is adjusted by a miniature potentiometer on the board.

LDR-Sensor has normally low output with light and goes high when covered (when the light is removed)

LDR-Sensor-L has normally high output and goes low when covered (when the light is removed)

Comment: Many of the HMS interface boards only report an input going low.  So select the version of the board that will be compatible with an HMS board and your mode of operation.

Comment: BrightSign's have a selection for High to Low or Low to High for the 'button event'.  So connecting to a BrightSign GPIO block will work with either version of boards.

Comment: The LDR (Light Dependent Resistor) is non polarized.  Cut the leads to length and insert into the pins provided.

Connections on the Light Sensor board:

• 0 = 0V
• S = Sense Output
• V = 3.3-5 Volts

Custom Configurations:

Contact HMS Electronics 'Technical Support' if you need the board configured other than shown.  I.E. with connector or LDR on the component side of the board.

Wire Identification:

• Pin 1 3.3V to 5V volts (3rd wire)
• Pin 2 Sense Output (middle wire)
• Pin3 Ground (0V) (wire with red stripe)

Cable Length:

The current draw on the sensor module is very low so cable length has almost no effect on sensor operation.  Maximum cable length has not been determined.  However, 100 feet (30 meters) is a distance that the module should work with.  We suspect that the sensor could be 300 feet (100 meters) or more.

Author: Richard Harkey
Revised: August 15, 2024