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• Should any pet be present and free in the installation area, it is suggested to carefully adjust
sensitivity, in order to avoid the risk of false alarms due to the passage of these small targets
in the areas which are very sensitive at the ground. To further decrease this risk, the height
of installation of the couple can be increased a little bit.
• Should trees or bushes affect the protection corridor because of the wind, false alarms
might occur. In the same way, if the system is installed near a hedge, this one must be
carefully attended to avoid darkening the protected area.
• High grass ad bushes decrease sensitivity at groud level.
• Any obstacle or important difference of level in the ground in the protected area, create
shadow-areas and very sensitive zones.
The BM M system has a good tolerance against bad weather conditions and temperature
variations; nevertheless it is necessary to care for following situations:
• RAIN: strong rain only causes a decrease of signal power whilst water puddles may increase
sensitivity at ground level
• SNOW: snow fall does not affect beams sensitivity, but the system cannot work if it is entirely
covered by the snow; so take care in areas with frequent and abundant snow
• FOG: a very thick fog can decrease the signal for 1/3. Because of the limits of compensation
of the gain automatic control (C.A.G.) , it is suggested to install the beams couple at a
distance not exceeding 85% of max range,in the regions where a thick fog is frequent.
The temperature working concditions are between - 20°C and + 55°C; if the use is required in
areas where temperature goes lower than 0°C, it is necessary the permanent installation of the
heating kit, which requires an alternate current at 12 V for a consumption of 150 mA for any
element of the beam (see chapter 15 for installation of heating kit).
