REFLECTOR TYPE PRODUCTS : The beam keeps producing false alarms

Check that if you cover the reflector a fault signal (steady yellow led light) is obtained. If this does not happen it means that the beam is pointed, even partially, towards an obstacle present along the route to be protected or that the beam is being reflected on some other surface (metal channels, pipes, windows or translucent walls etc.

If there are obstacles or reflective surfaces, first use the diaphragm filters for collimating the beam as well as possible and shield the receiver, at all times maintaining one square metre of space completely free, as needed for the infrared cone.

Check with the UTA instrument or with the ADM that the alignment has been carried out correctly, that the sensitivity threshold is correct, according to the Detector value reading on the instrument; the sensitivity calibration details are given in the individual manuals for each product line. To overcome problems of direct light sources or large reflective surfaces and to avoid direct reflections, you can install the system on a slight diagonal with the use of the manoeuvring and securing brackets.

The beam does not produce an alarm or shows a fault with the STF-4 filter

Check the beam alignment and the sensitivity threshold settings are correct. The alarm condition with the filter, using section A, is only obtained with the default sensitivity threshold. Follow the instructions on filter use in the user’s manual.

With the alarm test, the red led light goes on the interface or the beam relay is not tripped

The switching of the alarm relay only occurs when the LED on the barrier is flashing red. Normally the alarm check time is about 15 seconds. When tests are carried out, whether for fault or for alarm, remember to wait at least 40 seconds between one operation and another.


Always check that the installation height is at least 30 cm from the ceiling, as required in current regulation UNI9795. Compliance is also required with all the other current regulations.