Showing posts with label hazard. Show all posts
Showing posts with label hazard. Show all posts

Wednesday, July 30, 2008

CCTV Camera - Do-It-Yourself Installation Guide

by: Robert Moskal


Introduction:

This guide is written for those who do need video security and can't afford costly installation services, or if the CCTV installer is not available in your area - the later is more common than one could think. We will cover most common security equipment types, as it is virtually impossible to go over such a wide rang of different security cameras and recording/video processing equipment available on the market.

I assume anyone considering do-it-yourself CCTV installation has basic knowledge of wiring techniques and practices. I am not to be held responsible or liable for damages to the equipment due to mishandling or misuse. Remember; during the installation always pay attention to safety. Working at heights and using tools can be dangerous, please follow all safety practices. Lets jump right to it now.

Planning: First step of any camera installation is to plan camera and monitoring equipment locations. When planning for camera locations please take in consideration light condition, never install cameras in low light room pointing straight into the sunny area it will add glare to the picture, even if your camera has back light compensation it will not be enough. Use infrared cameras for very dark conditions and/or B/W cameras with as low LUX number as possible. I am not going to discuss proper equipment selection, as this was subject of my last article.

Selecting the best possible camera locations is not easy, and will directly impact the camera views. Besides light conditions, the distance to the monitoring object is equally important. There are many different types and focal lengths of lenses; your selection will depend on light condition and distance from the camera to the monitoring object. In small rooms around 500sq. ft. cameras with standard 3.6mm lens should be OK. Keep in mind that most bullet and board type of cameras come with 3.6mm lens, the greater the distance to the monitoring object the longer focal length of the lens will be needed. There is no ease way of judging lens selection, you can eider guess or buy professional lens selector tool.. Alternatively you can start with your lens selection and if needed get longer or shorter focal length lens later. Other option as far as lens selection goes, is to use variable focus lens, which is very versatile approach and takes the guess out of the lens selection process. For those who do not know what variable focus lens is, it's basically adjustable focal length lens that will allow to change the focal length within specified range, fore example: 2.6mm - 8mm or 5mm - 50mm.

To maximize cameras coverage and get the most out of the CCTV system for least amount of money minimize number of it by placing cameras in strategic places, unless complete area coverage is needed. Avoid overlapping camera views, do not install them with source of light directly in front of it and do not place infrared cameras pointing at each other to eliminate risk of overexposure. These are the most common mistakes that need to be avoided. After the initial camera locations are predetermined, lets look at cable placement. Make sure that it is actually possible and practical to run cable to each location, if running the cable to any camera location is for some reason impossible opt-out for alternate location.

Wiring: The most time consuming and important part of any camera installation is wiring. Plan your installation carefully to minimize cable lengths and insure good quality video signal. Never run cables alongside high power electrical lines, at least 12" spacing between video cable and power lines are recommended. Keep the cable lengths below 400ft and use good quality cable, most people take the cable for granted, but it is actually very important aspect of any installation. The CCTV system is only as good as its weakest component. I usually stick with RG59U with power Coleman cable (YES it is US made) sometimes called Siamese type cable. It is combo cable and will transmit video and power, as an alternative it is sometimes possible to use less expensive RG6 standard coax cable with separate run of 18/2AWG for power.

The Siamese cable is less bulky and easer to run, distribution power supply is recommended with this type of cable as power will be supplied from common place right next to monitor and recording equipment. Using Siamese cable makes for more clean and neat installation, as only one line is required for each camera. Running RG6 cable with separate run for power is the likely solution if power outlets are available near each locations. In this case individual plug in power supplies are used to power them with power cable running as separate and independent line to the camera. Both types of cables are available at dvrexperts. When running the cable it is good practice to leave couple of loops of extra cable at both camera and monitoring locations. This extra length of cable is needed if in the future monitoring or location will have to be moved slightly. After the cable is in place, the labor-intensive part of installation is over, now we can get to the fun part of installation.

Camera mounting: Most s come with mounting screws and bracket included, attach the bracket firmly and remember that in some cases different brackets than the ones supplied with the cameras could be needed.

Attach the camera to the bracket and adjust the position approximately at this time, we will come back to it later. Typical security camera is powered by 12VDC or 24VAC and power input type is screw or push terminals or 2.1mm plug. Power connection will differ for each type of power supply and input style. Most cameras are 12VDC, in this case it is important to observe polarity or you may damage the camera. The power cable has two conductors and in most cases it will be red or white and black cable. Use the red or white for positive and black for negative terminals. If it has screw or push terminals power input connect the cable directly observing polarity, if it is 2.1mm plug, a special 2.1MM Female DC Plug with Flying Leads have to be connected to the cable again keep attention to polarity. The 24VAC connection is very similar, with one major difference - polarity is not important.

Next step will involve some special tools and accessories. We will attempt to go over installation process of BNC crimp-on video connector, I will post video demonstration of BNC crimping techniques shortly so please check the web sites mentioned in this article often.

Steps: 1. Remove about 1/2-inch long outer jacket from the end of video cable exposing braid. 2. Slide the crimping barrel onto the cable with the larger diameter facing end of the cable. 3. Pull the braid backwards exposing the inner isolator material and remove 3/8-inch of it so you have now core conductor exposed. 4. The main part of BNC connector has a small hole on one side; push the exposed core conductor of the cable into that hole as far as it will go. 5. Push all the braid folded backwards in step 3 onto the BNC connector and spread the braid evenly around connector. 6. Push the crimping barrel onto the BNC connector all the way. 7. Using crimping tool, squeeze the crimping barrel onto the BNC connector, now the cable braid is compressed in between crimping barrel and BNC connector assuring secure connection.

BNC connector is on, lets hook it up now and repeat the steps for each camera, if you have purchased 16 camera system you may want to get some coffee first.

Monitor and recorder connection:

Cameras are on, its time to make final connections. I will focused on standard CCTV monitor, standalone DVR recorder and distribution power supply, as this is the most popular and likely solution for most CCTV installations.

First we have to install BNC connectors on this side as well - its time for that coffee again. It is good idea to make room for monitor and recorder now and setup some type of desk, shelf or rack to place all the equipment on.

We need the monitor and recorder in place so we can determine proper power supply location. Power supply should be mounted within couple of feet from the DVR video inputs. After power supply is secured separate the power conductors from the Siamese cable, and run it to power supply. Like we did with the cameras if 12VDC power is used, we need to watch the polarity, each terminal on the power supply is marked, so there should not be any doubt. Make sure the power supply is not plugged in to the power outlet yet.

Connect video cables to the DVR video in ports. We need one video cable to connect the DVR with the monitor, if you do not have one you may cut piece of Siamese cable separate the power conductors from it and install BNC connectors on both ends, you now have the cable. Connect the DVR monitor out port to monitor video in. We are almost ready to power up everything; there is only one more thing to take care before we do that.

We need to protect the equipment from power spikes by plugging it into power conditioner or better yet, buttery backup unit. If the installation location is experiencing frequent power outages, the backup unit is strongly recommended. To extend the backup time only plug the DVR and camera power supply to the backup unit and the monitor to regular power strip, this way if we do loose power for some time the DVR and cameras are still functioning as normal while monitor is off. Turning off monitor will not affect DVR and cameras in any way; it is actually good habit to turn the monitor of if not used to extend its life.

Power on and final adjustment: Yes... we are now ready to power it up for the first time, if this is your first installation it may be nerve-racking experience. Start with turning the cameras power supply on, turn the monitor on as well followed by DVR system. The stand-alone DVR, after self-test will show cameras or setup menu on first power up depending on your model.

To setup the DVR refer to the manual for proper settings. Go over each camera view to determine if the view is actually what you want, hardly ever it will be without additional readjustments. To properly and easily adjust the positions, the test monitor will be very handy if not essential tool. Go to each camera location and connect the test monitor to adjust the position to your preferences, if satisfied secure camera bracket adjustment screws - we will not go back to this camera anymore.

Conclusion: Congratulations! You have just completed your most likely, very first installation of CCTV system. Visit our store fore more information on surveillance cameras, DVR recorders, tools and accessories.



About The Author

Robert Moskal is Technical Department Manager at V2Comp, Inc., a major distributor of CCTV cameras and other surveillance equipment located in Chicago area. More information about new products can be accessed at http://www.amazingoutlet.com/


Cleaning Your Dryer Vent Means A Savings Of Time And Money And Avoiding a Fire Hazard

by: Rick Pocock

Have you noticed that its starting to take longer and longer for your clothes to dry? Does a load of towels now take 2 or 3 drying cycles, and maybe still feel a little damp? If so, you’re probably also paying higher gas and electric bills than you used to. The solution may be simpler than you think. And less expensive. Most people automatically think that the dryer itself is the problem, but it usually turns out that the venting pipe that exhausts the dryer to the outside of the house has become clogged with lint. If your dryer can’t vent out that heat and moisture in the clothes, then your laundry can’t dry. Over time, running the dryer this way will eventually create enough extra wear and tear on the dryer parts that it will ultimately lead to expensive dryer repairs. Worst of all, it also turns your dryer into a potential fire hazard.


Most dryers now have a safety feature that will either turn the dryer off or turn the dryer’s heat off if it senses that it’s overheating, which will happen when there’s a buildup clogging the venting system. That’s why it takes forever for your clothes to dry--the clothes will keep spinning but there’ll be no heat. This feature is not completely reliable to depend on, and the older dryers are also not as likely to have adequate safety systems which will shut it off or stop the heat. Who do you contact to get the venting system brushed out and inspected? Believe it or not, most appliance technicians will only deal with the dryer itself and want nothing to do with what it vents through. Generally the people to contact are chimney sweeps, and it is highly recommended to use one trained as a C-Det Certified Dryer Exhaust Technician if they are in your area. In addition to cleaning out the accumulation in the venting system, there are other ways to help keep you safe when using your dryer. One of the main causes for buildup in the dryer venting system is from forgetting to pull the pieces of paper, wrappers or Kleenex from the pockets before doing the laundry. Then add to that the hair (human and pet), sand, jewelry, money, and just about anything that you can think of, and you can see what it will lead to.


The more of this kind of stuff that can be caught ahead of time and not allowed to get into the dryer, the better. It’s crazy what winds up in there! In 1998, the last year reported, the U.S. Consumer Product Safety Commission estimated that there were 15,600 fires, resulting in 20 deaths and 370 injuries from dryer fires. The fire hazard, in many cases, is caused by the lint and paper that gets past the lint screen landing inside the dryer below the drum on the dryer floor. Have a qualified appliance repair person out to clean the interior of the dryer several times a year to minimize the chance of fire. Watch how the repair person does this. In some dryers, there’s an access panel in the front of the dryer that can be easily removed so that the homeowner can do this.


Clean the lint debris behind the dryer and keep combustible materials away from the dryer as much as possible. Lint should be removed from the lint screen before each load of laundry. In addition, the fabric softener pads or sheets are fine to use but they leave a chemical film on the lint screen which will make your dryer harder to exhaust. Every few months, take the lint screen out, bring it to your kitchen sink and wash it with water, liquid dishwashing soap and a tooth brush. The flexible connector hose between the dryer and the wall should be made from aluminum and not from flammable plastic. It should not be kinked or crushed, since this will also restrict the dryer’s ability to vent properly and will cause the dryer to overheat. It’s preferable that the connector hose only be long enough to go between the dryer and the wall with just a little bit of slack so that if the dryer is pulled out, the hose still stays connected. If your dryer is located in a laundry closet or small room, the door to that room must be open while the dryer is running. A dryer needs make-up air--whatever amount of air it’s exhausting out, it needs to bring the same amount of air in, without having to work for it. If the dryer cannot get that make-up air, it may overheat. A dryer needs at least 100 square inches of oxygen, the equivalent of a 10" x 10" window. Also, if there is an exhaust fan in the laundry room, the fan should be off when the dryer is running. Because of the high incidence of dryer fires, never leave the house if the dryer is on and never go to bed with the dryer running either. We are all a nation of multitaskers and what better way to multitask than to put wet clothes into the dryer, run some errands and come home to a load of dry laundry. This is really taking chances and just not safe to do. When looking for a company to clean the dryer vent system, make sure that the technician will use a brushing method to clean out the dryer venting system. Many companies simply use a vacuum or blower, which will not remove the lint accumulation in the venting system. This becomes that much more essential if the lint is moist, since it takes on a consistency close to paper mache and will otherwise stick like paste to the inside of the pipe. So if you are in need of this being done, just think about how much money you will be saving and how much joy it will put back into doing the laundry! Well, maybe that’s a slight exaggeration, but at least it will be a little less of a chore.
About The Author
Rick Pocock and his wife Terri have been in the chimney sweep and dryer vent business in San Diego, California for over 14 complaint-free years! Please visit
http://www.swedesweep.com and http://www.dryerventsbyswede.com for more information about the importance of having these services performed.