Guest LOC Posted August 14, 2005 Posted August 14, 2005 I am new to CCTV but have completed a few Ethernet cameras using P.O.E. My question is I want to use normal CCTV equipment and I want to use Cat5 cable (already installed). How can I do the following Power Camera Tx/Rx Camera signals Power seperate IR Power heater Power Blower What would be the best way to do this from one central point using their own power adapters?
breff Posted August 14, 2005 Posted August 14, 2005 You can use one twisted pair with baluns for the video signal, another pair for power (assuming 12v cameras) and another pair for tx/rx(although most ptz are 24vac and I dont think cat5 would be man enough to power them). As for IR, heater and blower, I dont see how you can power these without using a local power supply or running more cables. The spare pair in the cat5 could be used as negative triggers for 12v relays. The opinions I express are mine and are usually correct! (Except when I'm wrong)(which I'm not)
secboy Posted August 14, 2005 Posted August 14, 2005 For some one not in the trade your diving in at the deep end with this, we will need more info to steer you on this but I'm sure if you are patient the cctv guys will ask the questions and then give you the answers I'm just going to have a bath myself but the guys on this forem are very helpful and I'm sure they will come thru for you GOOD LUCK pAUL.
secboy Posted August 15, 2005 Posted August 15, 2005 I'm out of the bath! everything Breff said is fine but there are so many different ways of doing the same job you need to look the equipment you are using, for instance if you are using a PTZ set up and not a dome you will probably need an NVT type balun kit to transmit on cat5 but if you are using a dome you could use one which has the cat5 facility built in. Domes have there own psu's which power the camera and heaters within but PTZ 's can power these with 240v or low voltage you can power from a central point but you need to be aware of volt drop over cable length, dennard type domes need the psu within about 1meter of the dome. As you can see there are a lot of things to consider to be able to advise more info will make it easier,regards Paul.
Guest Rockford Posted August 15, 2005 Posted August 15, 2005 I am new to CCTV but have completed a few Ethernet cameras using P.O.E. My question is I want to use normal CCTV equipment and I want to use Cat5 cable (already installed). How can I do the followingPower Camera Tx/Rx Camera signals Power seperate IR Power heater Power Blower What would be the best way to do this from one central point using their own power adapters? 64542[/snapback] OK, you cannot do all of that using Cat5 for a bunch of reasons... Be very aware that if it exists in a "Catagory 5e certified structure", you will VOID the certificate if you transmit power of any kind over a C5e cable. Only Cat6 and Cat7 are IEEE certifiable in a PoE environment. Notice that even in this circumstance, it MUST be PoE (which I THINK is 802.1q -could be wrong) and not just power over the cable. anyway, with no C5e certificate, its not so much of a problem. It is "possible" but not "right" to transmit DC power over C5e. It is also most possible to carry video and PTZ telemetry in the same cable, but watch out for NEXT / FEXT if you're using voltages of any more than about 5VDC. You can completely forget about using AC on Cat5e cable. Doing this will definately product too much NEXT and will almost certainly affect video quality. when carrying ANYTHING in Cat5e cable, make sure that you stick to the pairs to ensure you reap the benefits of C5e's cancellation method. I don't think it'd be a good idea to run the video very far in C5e cable, especially if you're carrying other stuff in there too. C6 is better because it has a screen between pairs. My advice would be to run a shot-gun cable along the same run as the Cat5e and use that for AC power for the heaters etc and video and use the C5e cable for PTZ data and DC power. Hope this helps!!
Guest Rockford Posted August 15, 2005 Posted August 15, 2005 Further to my last, I was wrong: 802.1q is IEEE standard for VLANs! Power over ethernet is 802.3af.
Rich Posted August 15, 2005 Posted August 15, 2005 What TX/RX signals do you mean? Do you have power local to the cameras, ie 240v spur for each camera? What voltages are the items you want to use? What is the current draw from each item you want to use? Are the cameras internal or external? I am new to CCTV but have completed a few Ethernet cameras using P.O.E. My question is I want to use normal CCTV equipment and I want to use Cat5 cable (already installed). How can I do the followingPower Camera Tx/Rx Camera signals Power seperate IR Power heater Power Blower What would be the best way to do this from one central point using their own power adapters? 64542[/snapback]
Mavrick_001 Posted August 15, 2005 Posted August 15, 2005 Here's your best bet. Tell us all the locations of the cameras and distance from the control unit for each, then let us know what type of camera your looking to put in each location and we'll suggest how to do it and what your going to need to make it work CCTV Intruder Access Control Tony Hughes, Proprietor, TRADE MEMBER
Guest LOC Posted August 16, 2005 Posted August 16, 2005 Gents, it was not a project containing all these requirements in one unit, it was a question on how to do it. The project is now complete using coax and 0.75mm cable for power
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