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Re: CCTV with Cat5 and what I've learned.



On Friday, January 18, 2013 6:21:16 PM UTC+13, Jim wrote:
> A few weeks ago I mentioned that I was doing my first CCTV install using =
Cat5 and Baluns. I think it was here (but maybe in other groups too) that i=
t was touted as being less expensive to use Cat5 and Baluns compared to Coa=
x Siamese etc.=20
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> This is what I learned:
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> 12 cameras in a warehouse. Cameras draw 800ma max. Contrary to what the B=
alun people say their products will do ..... doing the calculations myself,=
(wire size, number of conductors, voltage drop, etc)theycouldn't/wouldn't=
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> "guarantee" that the cameras would work at the distances their advertisin=
g said they would. Their estimates of video distance was not my concern but=
 they had no idea that the Baluns could not carry camera "power" over the s=
ame distance. Since there are no outlets in the back of the warehouse (wher=
e most of the cameras are located) I had to use 24VAC supply with 1- amp ou=
tput each channel because there was more than a 10% voltage drop at the fur=
thest camera if I used 12VDC. $200.00 for power supply. Max safest distance=
 to keep cameras at less than 10% voltage drop is somewhere around 150 to 2=
00 feet. In order to do this, I had to inquire with the Balun mfgs/supplier=
s, how many of the Cat5 pairs were  used to carry power. No one that I talk=
ed to knew. They "assumed" two pair were used for video and two pair for po=
wer. Two pair for power would not stay within voltage drop spec at 168feet.=
 (my furthest run) So, I located Baluns with screw terminal connections, so=
 I could use three Cat 5 pairs for power and one pair for video. So that el=
imiated using Baluns with RJ45 connectors and required more time to untwist=
, strip, twist pairs and connect wires to termials, then it would take to c=
rimp an RJ45 connector for plugging into a RJ45 Balun. 12 Baluns @ $16.00 e=
ach plus shipping.
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> I also had to locate Baluns that had the power and video in/outputs on fl=
ying leads, because the Baluns with the BNC connectors attached would not a=
ll fit on the back of a 16 channel DVR if they had to be plugged directly i=
nto the connectors on the back of the DVR. But THEN .... even though you ha=
ve flying leads, you also cannot have 12 Baluns hanging off of the back of =
a DVR by 6 inch leads. They have to be mounted elsewhere, out of sight. (I =
didn't think of this until later) When using Siamese coax, you just have to=
 strip the power wires back and re-route them to the power supply and conne=
ct them directly to the terminals in the power supply and then continue the=
 coax runs to the DVR and and crimp BNC's on them. When using the Baluns th=
e Cat5 has to be run to where the Baluns are going to be located and untwis=
ted, stripped, twisted in pairs and attached to the screw termials on the B=
aluns. Then, using the hard wire adapter power plugs, it's necessary to run=
 additional wires from the Baluns back to the power supply. But now, since =
the Baluns are located "away" from the back of the DVR, it is necessary to =
manufacture BNC jumper cables from the video output of the Baluns to run be=
tween the location of the Baluns to the back of the DVR.
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> Behind the desk, mounted to the wall is a 12 x 12 x 4 inch plastic "jucti=
on" box containing the Baluns $15.00. Out of this box runs a group of power=
 cables from the power supply (mounted next to the plastic junction box.) a=
 group of Cat5 cables from the cameras and a group of BNC jumper cables goi=
ng to the back of the DVR. BNC connectors 12X2 @ .59each $15.00
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> I don't know if I'm missing something (?) I don't know if I've gone overb=
oard (?) but from what I see, with the additional parts and labor there's n=
o F....ing way it's cheaper to do a Cat5 with Baluns CCTV job compared to a=
 siamese wire job.=20
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> Comments please?

I've been doing this a long time & if you do a little ground work you can m=
ake life easy & profitable. I can complete a 16 camera instal (average size=
 premises) in one day. A few labor saving methods can make the instal a bre=
eze, keep it all uniform, tidy & professional. By using pre-made 20 meter s=
iamese cable 75-3 at US$4 + freight or 40 meter at US$6 from a decent manuf=
acturer your winning. These cables are BC foil shielded & braided. The pict=
ure is no different than RG59. I don't think digital HD is going to prevail=
 in the industry so you are best using 75-3 (minimum) as this cable can be =
used for the new HD-CVI systems available from Dahua both 720P & 1080P (bri=
lliant leap) These systems & cameras are cheap, HD, far more functional tha=
n previous systems. At cost of 4ch with varifocal 2.8-12 m cams for under $=
200 total & 1Mp (720P) you'd be stupid to instal anything else. Please don'=
t waste your time with cat5, it's not professional, it looks hacked, ridicu=
lous for servicing or troubleshooting & it's far too labor intensive. a dec=
ent cctv cable 20m should weigh 600grams & 40m at least 1kg. All of your sm=
art work is done in sourcing the cables, dvr's & cameras.


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