Tecwisen

Finally, let us compare both DVR-based CCTV systems and NVR-based CCTV systems with the following factors.  1. Cost  When it comes to cost a DVR-based based CCTV system is cheaper than an N VR-based based CCTV system. This is due to the NVR being more expensive than an equal DVR and equal-quality IP cameras are expensive compared to analog cameras in a DVR system. Alternatively, you may require an additional POE switch which may be needed to purchase with additional cost. 2.  Picture Quality Picture quality is higher in an NVR system. Cameras in  an NVR system produce higher-resolution pictures than a DVR system. Unlike analog cameras in a DVR system IP cameras produce digital images with digital image processing. Due to that fact, the picture quality is much higher in an NVR system. 3. Accessibility through network Although modern DVR-based systems can be accessible limitedly through a network best option for Internet accessibility is NVR-based CCTV systems. An NVR-...

The second type of CCTV system is NVR (Network Video Recorder) based CCTV system which is a network-based system.  Firstly let's recognize the main components of the NVR-based CCTV system.   Now let's see what are the basics of this system. Let's see more details later 1. IP Cameras As DVR-based CCTV systems, there are various types of cameras used in an NVR-based CCTV system depending on the purpose. But those CCTV cameras are called IP cameras as all cameras in an NVR CCTV system have an IP address. Unlike a DVR CCTV system resolution of the cameras in an NVR system is measured by megapixals. The picture quality of this system is mostly higher than a NVR based system 2. Network  Video Recorder (NVR)  Similar to the DVR in a DVR-based CCTV system. But unlike DVR cameras and NVR communicate by IP network in this system. The NVR only has one RJ-45 network slot to connect all the cameras. Communication between cameras and NVR is not done directly in this system. T...

1. Selecting a cable Selecting a good cable is essential for a reliable CCTV system. As there a several options Let's find out the advantages and disadvantages of each.   1. Coaxial cables Coaxial cable is the default cable that has been used to transfer video signals between the camera and video recorder since the very beginning of the introduction of CCTV systems. But using this cable has some disadvantages as well as advantages. Advantages  The loss of the cable is very low compared to other cables. Strength is relatively good Disadvantages Heavy and Bulky therefore difficult to install Need a separate way for camera power Cost is relatively high 2. CAT 5/CAT 6 network cables    Cat 5 or Cat 6 cables can be used for CCTV using passive video Baluns which convert a UTP cable near characteristics of a Coaxial cable. This cable also has its own advantages and disadvantages. Advantages Not heavy and is easy to install Both video signal and power can be sent throug...

 CCTV camera power supplies A separate 12V DC power supply is needed for CCTV cameras. Mainly there are two options in the market today. 1. Combined power supply  Can power number of cameras. Available in a number of current ratings. (eg- 10A,20A,30A etc). Can choose the current rating according to the number of cameras and the rated current provided by the camera manufacturer.  Advantages Easy to install Relatively low in cost Disadvantages If the power supply breaks down whole camera system stops functioning As some of these have fans these power supplies may be noisy  2. Single power supply   Used to power one camera. Separate units are needed to power each camera. Some units may equipped with backup batteries. Mostly installed near CCTV cameras.  Advantages Only one camera will stop working if one unit failed Disadvantages Cost is higher because several units needed  A separate AC power line is needed if installed near the camera 

 CCTV Monitors and Cables There were dedicated monitors for CCTV systems earlier and most of today's DVRs can use computer monitors, originally CRT-type monitors were used for this purpose. But nowadays LCD/LED monitors are widely used. CRT CCTV monitor LCD/LED monitor Cables used for CCTV Co-axial cables are generally used for DVR-based CCTV, but Cat 5 or Cat 6 cables can also be used. Cat 5, 5e, or Cat 6 cables are now commonly used due to convenience and low cost. When using Cat 5,6 cables, a device called Video Balun is used. This makes the Cat 5, 5e, or 6 cables a cable with the same properties as a Co-axial cable. This Video Balun is two types of Video Balun Active Video Balun and Passive Video Balun. Power should be provided for Active Video Balun and power should not be provided for Passive Video Balun. BNC connectors Coaxial cable Other types of cables that can be used  Passive Video Baluns

 Video Recorder A video recorder is an essential device in a CCTV system. Initially, analog video recorders with VHS tapes were used for this, and with the advancement of technology, digital video recorders are used today. Well, let's see what a Digital Video Recorder (DVR) is. Video in a DVR is recorded on a hard disk. DVRs are manufactured according to the number of cameras they can fit. (eg - 4 Channel DVR, 8-channel, 16-channel, 32-channel). And there are mainly 2 types of DVR. 1. PC-based DVR 2. Stand-alone DVR Any desktop computer can easily be turned into a PC-based DVR. But PC-based DVR is not very popular. Therefore stand-alone DVR is widely used. Stand alone DVR  Front view of a stand-alone DVR Rear view of a DVR and accessories    DVRs have many different features and below are some of them. 1. Remote viewing - This allows the DVR to be accessed remotely via the Internet (Remote logging). It can be viewed and controlled remotely from the cameras in this DV...