Guide to photocells for automatic gates

Important safety device (but not unique) let's see when it is mandatory to install them and how to do it correctly.
fotocellula e sicurezza

Table of Contents

Photocells are essential in an automatic gate system and are considered a very important safety device.

Photocells for gates represent the most widespread automated way to stop the closing of an automatic door, gate or barrier if there is an unexpected obstacle in its path such as a car, an object that has ended up there by mistake or even a person.

Why is it always recommended to install photocells for automatic gates?

Safety first. Unfortunately, every year there are still too many accidents involving people or vehicles due to a malfunctioning or badly installed automatic gate or because safety devices – like photocells – are missing.

In fact, it must be specified that type D devices, of which the photocells are a part, are not always mandatory: it depends on the “type of activation of the door”, according to what is established by “prospectus 1” of the EN 12453 standard and by EN 12445 .

the gate doesn’t fit the photocells or if those fitted are found to be defective, we risk not only damaging the gate itself but we also risk causing considerable damage to ourselves or to third parties.

Photocells are not the only safety system

The gate can be equipped with photocells (even more than a couple) to recognize the passage of people or objects but it should also be equipped with a device that reduces the impact force in the event of accidental impact, both in public and private areas, or that detects the presence of obstacles in the action area of ​​the sliding or swing gate.

So we can have:

Operation of gate photocells

Photocells for automatic gates are sensors that work with infrared rays that are invisible to the human eye.

Usually composed of transmitter and receiver.

They must be installed in opposite positions and in a straight line, with a recommended height of about 50cm from the ground, and strictly in pairs: one photocell is responsible for transmitting the infrared (the transmitter), and the other photocell is responsible for receiving it (the receiver) through the photocell element, often made of selenium, an excellent material for absorbing light impulses.

When the receiver stops receiving the signal, and therefore the beam between the photocells is interrupted by an obstacle, such as a car for example, the automatic gate stops avoiding hitting the element that’s interrupting the infrared.

If you want to learn more, here’s an article to dig deeper into the subject.

How to choose the right photocells for your system

The first thing to do is to check the voltage of your system. There are currently two different standards on the market: 12V and 24V.

It’s essential to choose a pair of photocells that share the same voltage as the motherboard of the system and therefore of the other components, in order to avoid causing malfunctions in the circuit or burning the photocells themselves.

VDS photocells are available in both types of power. If in doubt, you can get advice from our technicians too. They are also available in many different types and models:

  • Mirror photocells whose installation requires only a power supply access, since the infrared beam hits the disc of reflective material in a continuous manner. Once the obstacle between the photocell and the disc has been detected, the signal is “Blocked”

The second thing to do is to check the surface on which you are going to install the photocells. Remember that they must be installed in pairs, opposite to each other, in a straight line and that the optimal distance from the ground is about 50 cm.

Where to install photocells for automatic gates

Make sure that the pillar on which the gate rests, or if the wall on which it slides, has the necessary recesses and also make sure of their position considering your client’s needs.

You can always choose a photocell turret:

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