The Laser Photoelectric Switch GAB100M-AK-5V


Can i ask is this product immune to ambient light or in other words does it only detect the transmitter without interference from the sun? Is the sensitivity adjustable would be a very good feature?

Also im confused with the 3R laser specification. In the article below it states 3R is reserved for 5mW or less.


Hi Simon,

Looks like DFRobot have rated this for 65 meters so that suggests it would be reliable throughout that range. They have given it an IP66 rating, so it’s fair to say the 65 meter rating is suited for such environments.

I’m not sure why they refer to the 3R rating - although it does appear to have a 300hz modulated signal. Might be best to get in touch with DFRobot directly if you’d like more detailed information that is not listed on their Wiki.

Hi Graham

Sorry , I’m not sure what you mean when you mentioned distance in response to my question regarding sunlight interference ? I plan to have the laser and receiver only 1 metre apart but I was wondering if sunlight would set off the receiver and give false positives or can the receiver filter out sunlight? Reason why im asking is I’ve already built a receiver using a LDR with schmitt trigger however LDRs are very susceptible to sunlight and would very easily false trigger if exposed to sunlight through gaps in enclosures etc.

Additionally would you know what the “pointing angle” is referring to? it shows 3 degrees but is that from the centre axis to its entire spread of the beam. Reason why i need to know is im planning having two beams 50mm apart and they should not interfer with each other.

I tried to contact DFrobot but there website wont let me post to there forum (even though i registered) and i haven’t received a reply email from them.


Hi Simon,

The short answer is, I don’t know. I’m a maker though, and often datasheets are just a nicety. There are plenty of specs that suggest how this device is intended to be used, and we can read in-between the lines a little. This is an IP66 rated device and they claim 65 meters of operation. IP66 is typically an “outdoors” rating, so I can’t see how a sunlight is going to disrupt the normal use of this product, with or without sunlight. Sure there are some practical caveats, direct sunlight is a truck load of energy and is always going to be hard to compete with. Nothing a well designed enclosure won’t fix though, ensuring the receiver is always shaded from all angles from direct sunlight.

Pointing angle means the device will work with up-to a 3º error. I guess you’ll need to do some maths to figure out what the spread would be, include some safety margin (perhaps 1.5x the rated angle)

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