Pair of Compact Photo Cells A20-180

Great price. Came from Amazon Italy in about a week.

Fairly universal units will work with a wide range of voltages so should suit most applications. Both sender and receiver have lenses that rotate to allow for mounting on surfaces that are not normal to the beam.

First thing to say, I didn't buy this product from Amazon; they came as part of a complete, dual gate opener kit. Installation is increibly easy, but be aware that the back case of the device does flex a little, so make sure you mount it on a solid, even surface; not to do so, may mean the front casing will not easily clip on to the back case. Talking of the front cover/case, it is a push-fit arrangement; hooks in to the top edge and clips down on the very botton, side edges; reverse this process when removing. To be honest, I don't think it's meant for frequent removal (why would you?), so after setup, leave well alone! On both the pair of devices, you can rotate the PCB, on which the IR emitter/IR receiver are mounted; looks like they have an almost 180 degree of movement, which should mean that just about any installation is sorted. The TX unit only requires, typically, 24V from the controller and the RX, same power but also three additional wires to go to the controller. On power-up, there are no indicators on either unit to inform you, either that power is present or the beam is broken/made; if the two units are aligned-up, listen for the small relay (minature oblong box at the bottom of the PCB) on the RX unit to click when you BREAK the beam. On the alignment, exact line-up is not required, but do try and get them as closely aligned as possible.