Oh, The Pressure!

With today’s video technologies continuing to rise in complexity and cost, the pressure of making the right decision… well… The “pressure” here is not the pressure of decision, it is the decision of pressure.

Decision: A pressurized outdoor camera or a sealed outdoor camera (non-pressurized)?

Why have pressurized cameras?

Typically, the location of the camera will be in an area that is known to have some type of air-borne contaminants that could damage the internals of the camera. Contaminants can be anything from oil, water, or any particulate matter from manmade or natural occurrence. The thought here is that if the camera is internally pressurized above ambient pressure, these contaminants will be prevented from entering.

The core purpose of pressurization in an outdoor camera is to “ensure that no water, moisture or dust is able to enter the camera enclosure and cause premature failure of the electrical, mechanical or optical components.”

The above quote was taken from a previous blog entitled “Dry As A Bone” in describing the challenge of building an outdoor camera; to read the entire article click on the link below:

http://gotowti.typepad.com/my_weblog/2009/09/something-sidewinder-related.html.

The manner in which the seals are created for the Sidewinder P/T/Z camera is the same manner in which the seals are created for the all fixed cameras manufactured by WTI. A sealed outdoor camera (from WTI) meets the same core purpose as that of a pressurized camera; contaminants are prevented from entry.

Consider the maintenance cost reduction benefit of a sealed camera: no pressure checks! (Also, no alarm conditions when internal camera pressure drops)

Consider the installation site. Underwater (sea floor monitoring) or extreme altitudes (weather balloon) will indeed require some type of pressurized camera enclosure. Highways, intersections, utility infrastructure sites, building perimeter, etc… Why have pressurized cameras?

~David Scales, C.T.O.

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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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Digital Video Recorders and Network Video Recorders – save, store and playback.

A Digital Video Recorder (DVR) is a peripheral device that records information to a variety of storage devices (internal or external hard drive, USB port, a CD or DVD, etc.), digitally, from many sources. Some DVRs only record video but most will record both video and audio as well as other information (such as alarm functions). A DVR provides many advanced functions over the older standard - the VCR. These functions include video searches by an event, the specific time, a specific date and by each individual camera.

With a DVR there are many different video quality and frame rate options so that the user can optimize the disk space for their specific needs. DVRs can be set to automatically overwrite the oldest footage on the disk when the disk becomes full so that recording does not cease just because the internal hard drive has no more space. Most new-model DVRs will also allow the user to set up remote access to the security footage that can be called up over a web browser from any PC. Software packages are starting to come put now that even allows users to call up their DVRs right on their cell phones.

An NVR, on the other hand, is a Network Video Recorder which is hooked up directly to a network and is totally IP based. NVRs are extremely flexible since they are managed remotely over a LAN and they can simultaneously record and allow access to live video streams from the IP cameras connected to it. NVRs usually feature recording and playback capabilities, intelligent motion detection, P/T/Z camera control and a user-friendly GUI.

A NVR has some similarities to a DVR, but those similarities are limited to the fact that they both record and playback video. An NVR is a true digital system. NVRs receive digital images/video/audio over the network and record them digitally to a hard drive; while DVRs can accommodate both digital and analog cameras.

NVRs are becoming the more popular storage device because they can accommodate a larger number of cameras, they are easily integrated into existing systems, and they are incredibly flexible since they have no dedicated monitors or keyboards and all management and viewing takes place over the network on a PC.

WTI offers a wide variety of both NVRs and DVRs – check out our selection online at http://www.gotowti.com/Products_DVRs.htm or take a look at our entire line of solutions at http://www.gotowti.com/Products_Main.htm.

~The WTI Team

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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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Dry as a Bone – How the Sidewinder Camera Gets It’s IP67 Rating

One of the primary challenges of building an outdoor camera is trying to ensure that no water, moisture or dust is able to enter the camera enclosure and cause premature failure of the electrical, mechanical or optical components. Analyzing every nook and cranny that could allow moisture to enter the camera and then engineering an effective solution requires a little creativity and sometimes a little counter-intuitive engineering to achieve the best possible seal performance. Let’s take a look at the various water entry points and the sealing solutions that allow the Sidewinder to be able to be immersed in 1 meter of water for 30 minutes and still remain bone dry inside.

Window Glass – Sealing the viewing window glass presents a bit of a challenge, as two materials with different temperature coefficients of expansion must be joined together. A silicone adhesive with a moderate Shore A hardness of 30 and a -60C to +205C temperature rating was selected. This allows the glass and aluminum components to expand and contract without placing undue stress on the seal interface. Note the shallow groove around the edge of the glass. This groove prevents shear force from delaminating the adhesive from the aluminum surface.

Front and Back Plate to Camera Tube Seal – Sealing the window face plate and the rear plate to the camera housing tube is accomplished using -45C to +120C temperature rated, Shore 65 hardness o-ring seals. The o-rings are greased with a -40C to +95C temperature rated silicone lubricant to provide an air tight and water tight seal. The o-ring seals mate with the precision machined surfaces on the inside front and inside rear of the camera housing tube.

Tilt Shaft to Tilt Seal Housing – The tilt seal housing incorporates five different seals to provide an air and water tight interface between the tilt drive assembly shaft, the main housing plate and the camera housing tube. Wide temperature range seals and wide temperature range silicone lubricants are also used in this assembly to provide the highest possible performance. The tilt drive shaft seal will withstand a 10 PSI pressure differential without leaking over the full -34C to +74C TS-2 temperature range. The four o-ring seals provide an air and water tight interface between the tilt drive seal housing and the main assembly plate of the Sidewinder.

Pan Shaft to Pan Seal Housing – The pan drive seals are arranged and perform in a manner similar to the tilt drive seals.

Cover to Main Plate Assembly – Sealing the Sidewinder cover to the main plate assembly was the most difficult of the design challenges in making the camera capable of achieving an IP67 water immersion rating. Since the length of the edges that need to be sealed is fairly long, a highly reliable method needed to be developed. Also, a method for applying the high joining force was required to be developed. Several gasket designs were tried until the current design shown was found to offer excellent performance. Instead of a wide gasket, which would intuitively seem to offer the best sealing performance, a narrow o-ring style gasket was found to offer much higher sealing pressures along the gasket ridge sealing surface, as the force of the cover screws holding the cover to the plate is concentrated into a much smaller surface area than it would be with a wider gasket. Aluminum reinforcement strips were added behind the flanges of the cover assembly to allow a much higher mounting force to be applied to the cover screws, ensuring a better seal. A special screw sealing compound is also used to prevent water ingress around the screws.

Power Supply Base Seal – The power supply base seal was actually pretty straight forward to implement. Since the main camera base structure is very heavy duty, large bolts could be used to apply the force necessary to get a highly reliable seal. A special laser cut gasket is used to seal both the mounting rim and the mounting bolts.

Bottom Egress Cable Seal – A water tight integrated cable seal and strain relief was used to seal the cable exit point on the bottom of the camera. A silicone sealant is used to seal the strain relief to metal housing joint. The strain relief provides a water tight seal around the cable itself.

Flying Cable Seal – The connector end of the flying umbilical cable must also be sealed, to prevent water from entering either the camera or the attached umbilical cable hanging down from it. The inside of the connector assembly is potted with an electrically compatible silicone sealing compound to prevent any water from entering the cabling system.

Sealing all of the various potential water entry points in a camera with moving parts is a much more challenging enterprise than it is for a fixed camera. It was necessary to develop several different approaches to solve all of the unique material interfaces that resulted from the operational requirements of the various components. In the end, though, it is very satisfying to be able to immerse the camera entirely under 3 feet of water and know that it is completely protected from any potential water damage.

~Dale Roche, Director of Engineering

WTI (Wireless Technology, Inc.)

www.gotowti.com or www.wirelesstech.com

Covert Video Surveillance

Covert video systems are wonderful for law enforcement agencies, monitoring employees, monitoring customer service, watching over your home and much more. Covert surveillance systems are one of the best ways to catch criminals at times when they believe their actions are going unnoticed and/or when no one is around. Almost anything can be converted into a covert camera – lamps, books, clocks, framed artwork, clothing; these systems have become so advanced that looking at these covert camera containing items you wouldn’t be able to tell them apart from the same items that did not contain camera systems.



Law enforcement agencies were among the first to adopt covert systems. Covert video can provide clear evidence for use in many different kinds of trials; many times the cases will not even go to trial once the video evidence has been viewed. These kinds of systems are ideal for drug or illegal firearms sting operations, interrogations of criminals in custody, they are also becoming a staple of every patrol car on the road for a variety of uses.

Employee theft is also becoming a more serious problem. Employers can use covert surveillance systems to make sure that people aren’t leaving the premises with company property or stealing money from the registers or safes. These systems are also great for making sure employees are showing up to work on time or making sure they aren’t goofing off during times they should be working. Employers can also use covert systems to monitor how their employees treat customers. Sometimes loss of revenue isn’t just the employee stealing, but rather a loss of an actual sale from employees treating customers poorly.

Covert surveillance systems are also a great idea for homeowners worried about burglars. Systems can be set up to transmit to a monitor for simple viewing or a digital video recorder where the video can be recorded and stored. People can check in on their home surveillance systems while they are out on vacation using a computer with internet access and even on their cell phones. These kinds of systems can also be used to monitor the neighborhood directly surrounding one’s home; for example maybe you suspect the neighbors next door of illegal activity or someone in the neighborhood has been repeatedly vandalizing your home or the home of a neighbor. With a covert outdoor system, maybe hidden in a birdhouse or in a tree, these kinds of questions can be easily answered and those responsible can be brought to justice.

Another good in-home use for covert surveillance is to monitor people that may not be entirely trustworthy. By that I am referring to things like the “nanny-cams” to watch over the caretakers of your children. Maybe there are kids in the house that are old enough to be left alone after school in the home but the parents still want to keep an eye on them. There could possibly be some suspected domestic abuse with other people living in the home or a roommate that is suspected of doing something they shouldn’t be.

WTI has been creating covert systems since the company was founded… however, to get more information on these kinds of systems you will need to speak with one of our “Solutions Specialists” as all covert systems are custom made to exact specifications for each customer. There are many ways to contact WTI: http://www.gotowti.com/ContactWTI.htm or call toll free 866/gotowti (468.6984).

With so many uses, it’s no wonder that more and more covert surveillance systems are being installed everywhere.

~The WTI Team



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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

http://www.gotowti.com/ ● http://www.wirelesstech.com/

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Pierce Manufacturing + WTI’s Sidewinder camera = great partners!

Pierce Manufacturing is one of the world’s largest fire truck, mobile command vehicle and military truck manufacturer; they have been building fire and military vehicles since 1913 in Appleton, Wisconsin. They are always on the cutting edge of technology and an innovator in the industry, building each of their trucks from the ground up. They manufacture everything from the chasse to body of the vehicles and they install the pumps, sirens, lights and paint the vehicle so they are fully ready for service once they are delivered to the end user.



Pierce has installed many of WTI’s Sidewinder cameras on the fire truck and command post vehicles that they build. The Sidewinder is a color day/night, pan/tilt/zoom camera with 360° rotation on both pan and tilt axes. There are 3 different versions of the Sidewinder camera currently available: Standard Definition, High-Definition and the newest member of the Sidewinder family, Thermal Imaging.



WTI’s Sidewinder cameras have played a big part in the fire and command post vehicle industry. With the 35X optical zoom, the standard definition Sidewinder camera can zoom in on hot spots and/or monitor large events for injuries or other medical incidents. The thermal imaging Sidewinder can see through fog, dusk and smoke so they can find hot spots and injured victims in a burning building. The high-definition Sidewinder provides crisp, clear, detailed video to monitor large events.



Pierce recently installed both a Standard Definition and a Thermal Image Sidewinder on a command post vehicle for the Amir of Qatar. This command post is equipped with the very latest in high tech surveillance and communications; it will be in attendance at every major event in the area to insure high levels of security and safety for all people.

Pierce has recently installed a Sidewinder on a brand new Frisco Texas Fire Truck. The Frisco Fire Department was so impressed with the Sidewinder’s performance that they are installing a High-Definition and a Thermal Image Sidewinder on their new command post vehicle that will be featured at this year’s FRI (Fire-Rescue International) show held in Dallas Texas on August 28th and 29th.

Pierce is always thinking ahead for the improvement of the fire fighting industry. They are currently working on a solution to transmit video wirelessly from the top of an aerial truck ladder to the firemen on the ground for enhanced views of the emergency scene to allow faster maneuvering to put fires out and save lives. More to come on that!

~Lester Miyasaki, National Sales Manager



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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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