Condensation in CCTV cameras is an underestimated threat

When designing systems, many important factors are taken into account. The risk of condensation forming inside the case is clearly not a concern. And in vain. The video surveillance system has its own work cycles, which are superimposed on daily and annual fluctuations in temperature and humidity. A certain combination of conditions can cause unpleasant effects that can call into question the suitability of the system for use. For example, at a moment critical for the safety of an object, the operator will see something vague and incomprehensible on the screen instead of a “picture”.

Once the Paket CCTV Murah company tested several budget Chinese cameras, and it occurred to someone to leave one of them on until the morning. The device stayed overnight on the windowsill with the IR illumination on. The employees who came to work first opened the window to ventilate. After a while, we discovered that the glass of the casing had fogged up from the inside - in a chamber hermetically sealed and passed through an OTC in distant China. Accidentally? We connected three more cameras from the same vendor - the result is the same. Marriage? But we are violating the sealing of the casing for access to the memory card slot and the reset button, so claims against the manufacturer are inappropriate in this case.

The most unpleasant thing is that this can happen with any camera on any object. And the matter may not be limited to just one blurry picture and unusable records in the system. The systematic appearance of condensation is fraught with corrosion of electronic circuits, components and connectors - that is, the failure of the camera.

How to be? In addition to the careful selection of the manufacturer, models and versions of the chambers, it all comes down to a thoughtful and skillful installation, timely care of the chambers (cleaning, changing seals, using a sealant) and some unobvious tricks.

Where does it come from?

The physics of the process is quite obvious - we are dealing with the condensation of water vapor from the air mass contained inside the casing. For water droplets to fall on the glass, it must be colder than the inside of the chamber. Outdoor cameras are subject to temperature fluctuations, which is quite natural. The maximum differences in temperate climates are observed, as a rule, in late summer and during the fall. In harsher weather conditions, water constantly "attacks" all the inputs and outputs of the enclosure, and the likelihood of moisture condensation on the optics increases.

Dew fall from the inside of the casing is also possible in carefully sealed chambers, if the humidity inside is increased for some reason. Therefore, the first and most obvious step to getting rid of the problem is to make sure you have street cameras installed in your outdoor facility. That is, with a housing with a protection class of at least IP65. Yes, they are more expensive - but the savings in this matter will come out sideways. Moreover, cheap "street people" are not always reliably protected: manufacturers also like to save money, but they do it in different ways.
How to fight?

To "cure" a camera suffering from condensation on the optics, it must be dismantled and brought into a dry room. Work on site should only be done as a last resort. The procedure for removing condensation itself is quite simple: wipe the window or dome with microfiber cloths - they do not leave drops. Wiping the front lens is not recommended as it may damage the coating. Please note that moisture can accumulate in other parts of the enclosure; do not be too lazy to wipe dry there too. Alternatively, you can use a hairdryer. Such drying will remove moisture from the lenses, but requires care: there may be plastic parts in the camera that can melt if overheated.

Experienced people advise treating the transparent inner surfaces of the casing with an anti-fog spray, which reduces condensation formation. At the end of the wiping, drying and processing procedures, the chamber must be closed using standard gaskets. They may need to be refurbished and, where necessary, a sealing gel applied.

A desiccant sachet can be an effective solution - usually silica gel is used for this purpose. However, it should be remembered that the capacity of the absorber is limited, and at some point it will stop working and will need to be replaced. The frequency of this procedure depends on the climate, time of year and the specific conditions of the site. Some budget camera manufacturers initially put silica gel inside the case - however, it's better not to hope that someone else will do everything for us. In our practice, there was a case when, in a large batch of chambers, containers with a desiccant were ... tightly sealed. Employees of the supplier company had to urgently disassemble each chamber, shake out the bag from it and manually pierce it with a needle.