Claudio Catanzaro 0 Posted June 21, 2007 Hi, I've made a 8 cameras installation with a dvr card. It Worked for 3 or 4 months and the card got fryed, and the guys who sold it to said that was for a faulty camera. One camera was giving more tan 2 volts via coax, and a friend who help me with the install told me that he remembers feeling electricity when he was adjusting focus for one of them. Now I have bought a new card via Internet and I want to be sure that It will not be fryed too. What do I need to check to be sure that my installation is fine? Voltage? Impedance? Amperage? and how much of each one can a CCTV device afford without have some injure? I'm not talking about a bad picture or weak signal but about something that can damage some equipment. Thankyou for your answers Claudio Catanzaro P.D. Some litle sins that I made in this installation : - I Used RG6 coax cable. - I Made a "patch panel" with rg6 "twist on" connectors mounted in two rails (I will check tomorrow if I didn't mixed braids in the pannel). - Cameras has differents grounds (I hadn't bad signal, pictures were perfect!) - Bigger cable has less than 90 ft. (that's not a sin ) - Four cameras (110 mA each) share a 12 V 500mA DC reg power supply. - Some cameras are in a industrial enviroment, sharing electrical circuit with welding machines and plastic injectors - All cameras has 12 V 500mA DC reg power supply (some of them sharing it) but not all of them are behind a UPS or voltage regulator. Share this post Link to post Share on other sites