Hybrid Solar Lighting
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A discovery channel segment on Sunlight Direct’s fiber optic sunlight transport system.
El Universo: Fenómenos cósmicos
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Examinaremos la variedad de fenómenos cósmicos que han tenido efectos tanto positivos como negativos en la vida de nuestra Tierra. Desde la belleza de la Aurora Boreal y los arco iris, a los peligros de la radiación de rayos UV y los rayos cósmicos, desde el milagro de la fotosíntesis a la emoción de la lluvia de meteoritos, en este espacio examinaremos cómo los efectos generados por el Sol y otras fuentes extra-solares pueden introducirse literalmente bajo nuestra piel, desbaratar nuestra tecnología, hacer posible la vida y amenazar nuestra existencia, todo al mismo tiempo.
Countertop Installation Wrinkle Retinol Platinum Visa Credit Card
CCTV Camera – Do-It-Yourself Installation Guide
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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.
Acetal Spur Gear With Brass Insert 20P 20 Degree Pressure Angle, 30 Teeth x .250″ Bore x 1.500″ Pitch Diameter
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Acetal Spur Gear With Brass Insert 20P 20 Degree Pressure Angle, 30 Teeth x .250″ Bore x 1.500″ Pitch Diameter
Acetal Spur Gear With Brass Insert 20P 20 Degree Pressure Angle, 30 Teeth x .250″ Bore x 1.500″ Pitch Diameter Feature
Acetal Spur Gear With Brass Insert 20P 20 Degree Pressure Angle, 30 Teeth x .250″ Bore x 1.500″ Pitch Diameter Overview
Acetal Spur Gears with Brass inserts have the advantage of being quiet, non-corrosive, lightweight and shock resistant. Useful for both continuous movement and in static control systems where only a quarter or half turn is made. They may be used in train with brass, steel or cast iron gears. Furnished with bored hub – but not drilled for pin or tapped for set screw. Color: Natural.
Acetal Spur Gear With Brass Insert 20P 20 Degree Pressure Angle, 30 Teeth x .250″ Bore x 1.500″ Pitch Diameter Specifications
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How To Make Solar Panel At Home-Learn How To Make Solar Panel At Home
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The best thing about solar power is that it has an unlimited potential. Learning how to make solar panel at home is neither technical nor costly; in fact you can easily solar power your complete home for a very small and affordable investment. You just need to know how to make your own renewable energy source and today I am going to tell you exactly how to make your own solar panel at home.
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