CCTV Wiring System for a building

[jaaan44 0]

Was hoping somebody would enlighten me about a wiring issue in the installation of a CCTV System for a building.

 

-Suppose you have a 3-story building.

-For each floor you have 16 cameras.

-Siamese cables are used (RG59 + power cord)

-The 3 16-channel DVR's are located on the 3rd floor.

 

How will i go about installing the wiring for each camera?

Should the cables run from the camera directly to the DVR? or

Do i have to build a junction box/wiring closet to every floor of the building where the connections will terminate, then make a connection from that particular floor's junction box and connect to the DVR on the 3rd floor?

 

Our current setup is just connecting all cameras in the building directly to the DVR. Not sure if that's the appropriate approach though.

 

Any help would be greatly appreciated. Thanks. =)

[VST_Man 1]

- use 24VAC.....better than 12vdc

- keep all RG cable runs less than 250ft. if longer, use CAT5 & Baluns

- observer cable install rules; keep away from power, lights, ect.

- if RG cable runs are longer than 250ft. you can also install powersupply boxes closer to the cameras which will extend the RG cable run. Not my prefered method but it works.

 

yes you should make all your cable run direct to the DVR. junction boxes are ok but more work/parts.

 

16 cams per floor is alot of wire at the DVR so you may want to consider placing a DVR on each floor and then network them to the main room. I also have seen this type of setup screwed up when they install all in one main room , usually the Hotel Managers office, which turns his office into a "hot box"...........and a wire hell room. hard to fix 1 camera in a area like that............

 

take a look at IP cams & PoE. as long as you build a seperate network with a minium Gig at the DVR............all is good. Technology is here and any future camera upgrades will require a network as analog is becoming "old school". May as well build the network now so you can upgrade later? If you choose a "NVR" approach, start with the NVR first and then match it to the cameras first...........don't buy cameras and then try to find a NVR. Video Insight has some beefy IP cam solutions. I just installed 8 IP NVR servers in FL that are doing very good.

[bigbuilding 0]

definetely want some junction boxes to allow easy access for possible future expansion

[Soundy 1]

Personally, I'd probably go with a separate power supply for each floor, to reduce the losses (especially for the furthest floor from the DVR). Since the cable is likely to route through or near each floor's electrical or phone room, that gives you a good spot to locate each floor's supply.

 

While one uninterrupted run from camera to DVR is generally preferred, of course, having a separate PSU per floor negates running siamese cable for the entire length of each run, and probably means a junction box for the video feeds in the same vicinity as the PSU.

 

Frankly, what I'd probably do in this instance, is use Cat-5e and baluns all the way. You can run one Cat-5 to each camera, terminate to RJ-45s, and use baluns like these to easily split out the video and power. You can then use four of these and run all 16 video feeds over four Cat-5e from each floor to the DVR locations, then use four of these (per DVR) to split that back out into the 16 video signals into the DVR.

 

That's the "clean" way... or you could just take the video pair from each camera and splice it to a pair of the floor-to-floor "drop" runs (use a punchdown block to allow for better future flexibility), and split it out at the DVR same as above, or just using four individual baluns.

[jaaan44 0]

Thanks a lot guys. These are really VALUABLE inputs. I have a few additional questions though:

 

1. If connection requires more than 250ft, why should we settle for Cat-5e and baluns? Is Cat-5e better at transmitting video signals than RG cables?

 

2. Is it ok to run network cable runs, PABX lines, and surveillance cables in the ceiling in one cable tray?

 

2. I was thinking of putting up wiring closets for each floor, these closets will house all network cables, Pabx phone lines, and surveillance cable terminations (for future expansion purposes). This is where i intend to put the junction box for the surveillance cable for each floor. You think this is a good idea?

[Soundy 1]

1. Depending on the specific balun type and manufacturer claims, video over balun-and-cat-5 is good for anywhere from 1000' to over a mile.

 

2. Sure. I'd be sure to keep all of them well away from any EMI sources, and especially away from parallel runs with AC wiring, but that's just good practice any time.

 

3. That's an excellent idea. One company I used to work in, their head office had a huge panel of BIX terminals in every floor's comm closet, a bundle of runs from there to each workstation, and a single- or dual-gang box at each workstation with interchangeable comm jacks - each station could be given any combination of phone, ethernet, or token-ring (yeah, this was quite a while ago) that was needed, with the appropriate patching done via the BIX panel. Need to add another network drop? Just plug in the appropriate jack insert at the desk and punch down the appropriate wiring between the station terminus and the network patchbay. They used a similar setup at every one of several dozen "field offices" as well. It was a really effective and flexible system.

[scorpion 0]

Soundy hit that one on the head!!

 

I know it is redundant to say, but I would say to have each with it's own color of cat 5.

 

Network, PABX, Surveillance ect.

 

If you have multiple colors in a wall plate then it is easier to install, troubleshoot, upgrade ect.

 

At a minimum having PABX color, and network color, and cctv color makes a big difference if you do not feel like buying cases of every color to have each network cat 5 color coded.

 

I hate playing around when every cat 5 is blue for all systems! Yikes!

[Soundy 1]

Yeah, different-color Cat-5 for each application is a great idea too, although if you need to, say, re-use a phone run for network or something, it kinda blows your color scheme A better idea is just to make sure everything is labeled properly - the aforementioned site I was on, every workstation was numbered, every jack at the workstation was numbered, and every bix section was numbered to match as well. (They also had only Cat-3 to a lot of stations in the more remote field offices, and yes we successfully ran ethernet over that in most cases - it had been running token-ring before, which was nowhere near as picky).

 

Of course, in theory your CCTV runs will be completely separate from any workstation network/phone runs, so two separate colors for those purposes is still a good idea!