Security Dealer & Integrator

JUL 2018

Find news and information for the executive corporate security director, CSO, facility manager and assets protection manager on issues of policy, products, incidents, risk management, threat assessments and preparedness.

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24 Security Dealer & Integrator / July 2018 and the front lens/ window of the cas- ing should be com- pletely flat to make it difficult for snow to build up. Even with good design and speci- fications, frost and snow is some- times unavoidable when operating in extremely low temperatures at high speeds. One solution is to add a heater for the front lens/window of the casing. Quick and even heating is normally achieved by ensuring the heater goes all the way around the screen, as opposed to plac- ing a heater at the bottom. In addition, a highly reliable heating method is required, which is usually achieved by using a printed circuit board (PCB) that enables the heater to be activated using a digital power switch as opposed to a less-reliable mechanical switch. Tempered glass has many advan- tages over plastic and normal glass, as it will withstand weather extremes much better, and will not become dis- colored over long deployment periods – thus making it essential for exterior train surveillance. 3 Water resistance: Technology has evolved over the years to help protect cam- eras reliably in outdoor environments; however, in order to guarantee a cam- era remains waterproof on the exterior of a train, several additional factors must be considered. IP66 and IP67-rated cameras are both designed to withstand heavy rain; however, IP67 cameras are also designed to withstand pressure. us, choosing IP67 cameras is advanta- Video Surveillance geous when deploying on trains that travel at high speeds and encounter heavy rain. It should also be noted that tests for IP66 and IP67-rated cameras simulate different scenarios that can be experienced on the outside of trains. For train customers demanding extra reliability, integrators can choose cam- eras with both IP66 and IP67 ratings. 4 Condensation: e envi- ronmental conditions on the exterior of a train can lead to condensation inside a camera – oen because of the heat generated by its processor. When the temperature out- side is cold, the difference in inter- nal temperature of the camera causes condensation to form on the inside of the camera. Even cameras with an IP68 rating are only dustproof and waterproof and cannot protect against humid air traveling from one side of the glass to the other. Since high ingress protection alone is not sufficient to prevent conden- sation forming on the inside of the camera, the best way to overcome this problem is to use a protective coating on the inside of the front of the camera that prevents condensation. Challenge: Prevention of Corrosion and Scratches A scratch-resistant casing should be deployed on any cameras mounted on the exterior of the train to protect against getting damaged or broken. Avoiding corrosion is particularly important, because the cameras are constantly subjected to conditions such as pollution, acid rain or salt water, and it is critical that they do not develop any weak points because of corrosion. Smart manufacturer design is the first step to corrosion prevention. e shape of the camera should not have any sharp angles, which can produce weak points in the protective coating and cause it to peel away – leaving the camera exposed to the elements. e casing of the camera should be coated with powder paint because it offers the hardest finish; however, if too little coating or treatment is applied, the camera will not be suffi- ciently protected against corrosion, whereas too much coating will destroy its smooth finish – thus making it less resistant to water. Screws and fasteners are another key area of consideration when it comes to Casings and enclosures help keep cameras protected from the elements. Photo: Wikimedia Commons

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