Operating temperature
The temperature range at which the intercom is able to work normally.
If the device is installed in a residential area or office, you can not pay much attention to this parameter: the temperature in such an environment rarely goes beyond +18 ... +25 °C, such values are normally tolerated by any intercom. But if the device needs to be placed in a "non-standard" microclimate — for example, an unheated warehouse, where conditions do not differ much from outdoor ones, or a production workshop with a high temperature — you should make sure that the chosen model can normally endure such conditions.
Separately, we note that even the most “heat-resistant” intercom cannot be exposed to prolonged exposure to sunlight.
Operating temperature
The range of air temperatures in which the call panel maintains normal performance.
Outdoor panels installed outdoors and in unheated rooms are subject to the greatest temperature fluctuations, therefore, it is with this installation that this parameter should be paid special attention. At the same time, we note that even the most “heat-resistant” models must be protected from sunlight. If the conditions in the room are comfortable for people all year round, then they will be quite normal for the call panel, in such cases you can not look at the operating temperature at all.
Horizontal viewing angle
The horizontal viewing angle provided by the camera on the entry panel of the intercom.
This parameter has a double meaning: other things being equal, a wider field of view allows you to cover more space, but reduces the size of individual objects in the frame. So it’s worth choosing according to this indicator, taking into account what is more important for you — good visibility on the sides or an additional degree of increase. As for specific values, in modern outdoor panels they can vary from 50° (directional cameras) to 166° (ultra wide-angle lenses with a minimum of dead zones on the sides).
