CCTV using Baluns

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I'm starting a CCTV job tomorrow in a small (30K sqft)warehouse using analo=
g cameras over cat5. Up till now I've used siamese coax and 12vdc. I typica=
lly do more residential work than commercial so I usualy don't have to worr=
y about voltage drop.=20

On this system I'm installing 10 inside cameras all with IR LED's. Each cam=
era draws 700ma with IR LED's on. I've got 5 cameras that will be in the re=
ar of the warehouse where there are no power outlets so the cameras will be=
 aprox 100 to 150 feet from the 24vac power source. I bought Balun's with s=
crew connections (rather than an RJ45 connector) for the Cat5 so that I cou=
ld use six of the conductors for the power, giving me aprox a 19 guage wire=
. I figure that should give me a voltage drop of about 2 volts which is les=
s than 10% of 24volts required by the cameras. I didn't do any research on =
what affect the distance of 150 feet over a 24 guage wire would have on the=
 video signal. I don't think it'll be a problem but I can always switch one=
 of the voltage wires over to the video terminals.=20

I'm just looking for some comments, suggestions and possible problems that =
I might not have thought of when using Baluns and Cat5 Any comments about l=
onger distances using Cat5 would be appreciated also. I've got a couple mor=
e larger warehouse jobs coming up so voltage drop is going to be a bigger i=
ssue

Re: CCTV using Baluns
On Wednesday, January 2, 2013 10:38:37 PM UTC-5, Jim wrote:
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cally do more residential work than commercial so I usualy don't have to wo=
rry about voltage drop.=20
Quoted text here. Click to load it
rear of the warehouse where there are no power outlets so the cameras will =
be aprox 100 to 150 feet from the 24vac power source. I bought Balun's with=
 screw connections (rather than an RJ45 connector) for the Cat5 so that I c=
ould use six of the conductors for the power, giving me aprox a 19 guage wi=
re. I figure that should give me a voltage drop of about 2 volts which is l=
ess than 10% of 24volts required by the cameras. I didn't do any research o=
n what affect the distance of 150 feet over a 24 guage wire would have on t=
he video signal. I don't think it'll be a problem but I can always switch o=
ne of the voltage wires over to the video terminals.=20
Quoted text here. Click to load it
 longer distances using Cat5 would be appreciated also. I've got a couple m=
ore larger warehouse jobs coming up so voltage drop is going to be a bigger=
 issue

I have been using baluns since they came out and actually think you get a b=
etter picture on long runs than coax

Re: CCTV using Baluns
On Friday, January 4, 2013 6:41:58 PM UTC-5, NickMark wrote:
Quoted text here. Click to load it
ver cat5. Up till now I've used siamese coax and 12vdc. I typically do more=
 residential work than commercial so I usualy don't have to worry about vol=
tage drop. > > > > On this system I'm installing 10 inside cameras all with=
 IR LED's. Each camera draws 700ma with IR LED's on. I've got 5 cameras tha=
t will be in the rear of the warehouse where there are no power outlets so =
the cameras will be aprox 100 to 150 feet from the 24vac power source. I bo=
ught Balun's with screw connections (rather than an RJ45 connector) for the=
 Cat5 so that I could use six of the conductors for the power, giving me ap=
rox a 19 guage wire. I figure that should give me a voltage drop of about 2=
 volts which is less than 10% of 24volts required by the cameras. I didn't =
do any research on what affect the distance of 150 feet over a 24 guage wir=
e would have on the video signal. I don't think it'll be a problem but I ca=
n always switch one of the voltage wires over to the video terminals. > > >=
 > I'm just looking for some comments, suggestions and possible problems th=
at I might not have thought of when using Baluns and Cat5 Any comments abou=
t longer distances using Cat5 would be appreciated also. I've got a couple =
more larger warehouse jobs coming up so voltage drop is going to be a bigge=
r issue I have been using baluns since they came out and actually think you=
 get a better picture on long runs than coax

Hi Nick,

What I'm looking for is how you run the power. I can see that it's convenie=
nt to run the Cat5 wire and less expensive but when you start trying to pul=
l 700ma for cameras over 150 feet of Cat5 wire, there are questions that ar=
ise about voltage drop. When doing a residence, it not convenient to have l=
ittle power packs plugged into outlets or to locate a seperate power supply=
 up in an attic someplace but it's unusual to find a run over 150 feet in a=
 home. However sometimes the same goes for commercial. The small commercial=
 that I'm doing right now doesn't have any electrical outlets in the back o=
f the warehouse but there's 6 cameras back there. I usually use 12VDC camer=
as but I chose 24VAC cameras for this job because of the voltage drop. I co=
uldn't find any of the Balun distributors that were able to tell me how man=
y of the Cat5 pairs were used for voltage and how many of the pairs where u=
sed for video in the Baluns with an RJ45 connector. I needed to know becaus=
e 700ma over 2 pair of 24ga wires at 150 feet is too much of a voltage drop=
 at 12VDC. So I located a Balun that had screw terminal connections instead=
 of the RJ45 for the Cat5 wire so that I could choose to use three pair for=
 voltage and one pair for video.=20

I'll let you know how my theory works out.

Re: CCTV using Baluns
Jim Wrote:

Quoted text here. Click to load it
cameras over cat5. Up till now I've used siamese coax and 12vdc. I typically do
more residential work than commercial so I usualy don't have to worry about
voltage drop.
Quoted text here. Click to load it
draws 700ma with IR LED's on. I've got 5 cameras that will be in the rear of the
warehouse where there are no power outlets so the cameras will be aprox 100 to
150 feet from the 24vac power source. I bought Balun's with screw connections
(rather than an RJ45 connector) for the Cat5 so that I could use six of the
conductors for the power, giving me aprox a 19 guage wire. I figure that should
give me a voltage drop of about 2 volts which is less than 10% of 24volts
required by the cameras. I didn't do any research on what affect the distance of
150 feet over a 24 guage wire would have on the video signal. I don't think
it'll be a problem but I can always switch one of the voltage wires over to the
video terminals.
Quoted text here. Click to load it
might not have thought of when using Baluns and Cat5 Any comments about longer
distances using Cat5 would be appreciated also. I've got a couple more larger
warehouse jobs coming up so voltage drop is going to be a bigger issue


I don't think you'll have any problems within 150'.  I switched to CAT5
exclusively for new installs a few years back.  It saves money on cable,
and it "future proofs" the install in case they want IP cams later.

I always use a different color cable than what their network is using to
avoid any confusion.  If the Ethernet network is using blue, I'll go
with yellow or something completely different so their network tech's
don't get confused.


Re: CCTV using Baluns
On Wednesday, January 2, 2013 10:51:20 PM UTC-5, G. Morgan wrote:
Quoted text here. Click to load it
2vdc. I typically do more residential work than commercial so I usualy don'=
t have to worry about voltage drop. > >On this system I'm installing 10 ins=
ide cameras all with IR LED's. Each camera draws 700ma with IR LED's on. I'=
ve got 5 cameras that will be in the rear of the warehouse where there are =
no power outlets so the cameras will be aprox 100 to 150 feet from the 24va=
c power source. I bought Balun's with screw connections (rather than an RJ4=
5 connector) for the Cat5 so that I could use six of the conductors for the=
 power, giving me aprox a 19 guage wire. I figure that should give me a vol=
tage drop of about 2 volts which is less than 10% of 24volts required by th=
e cameras. I didn't do any research on what affect the distance of 150 feet=
 over a 24 guage wire would have on the video signal. I don't think it'll b=
e a problem but I can always switch one of the voltage wires over to the vi=
deo terminals. > >I'm just looking for some comments, suggestions and possi=
ble problems that I might not have thought of when using Baluns and Cat5 An=
y comments about longer distances using Cat5 would be appreciated also. I'v=
e got a couple more larger warehouse jobs coming up so voltage drop is goin=
g to be a bigger issue I don't think you'll have any problems within 150'. =
I switched to CAT5 exclusively for new installs a few years back. It saves =
money on cable, and it "future proofs" the install in case they want IP cam=
s later. I always use a different color cable than what their network is us=
ing to avoid any confusion. If the Ethernet network is using blue, I'll go =
with yellow or something completely different so their network tech's don't=
 get confused.

Not necessary in this case but good idea to keep in mind=20
Thanks

Re: CCTV using Baluns
Quoted text here. Click to load it

I have used a few baluns, and for the most part have had good luck on the
video side.  I tend to be cautious though and stay at a max of about 75% of
the balun's rated max distance.  For powered and amplified twisted pair
baluns/hubs over longer distances distance is more critical as if you go too
much higher on distance rating you get an over voltage or over driving
signal on the video which can cause issues.  (Never actually checked the
precise why, but it isn't good.)

Now going old school.  I had some old b/w composite cameras going a couple
thousand (that right thousand) feet over RG6 copper cable.  (special order)
I had issue with voltage drop on the supply side so I went with higher
voltage transformers as needed.  It was marginal, but it worked, and I was
the only one who could make it work.   I didn't need any video amplifiers
either.  Waaaaaay out of spec, but the video was adequate to drive the
multiplexor and recorded adequately on the VCR.

You do know that RG-59 copper and 18/2 is used all the time up to 750'
right?  At one time one of my vendors was selling it in 750' spools instead
of the more common 500' or 1000' spools.

One of the nicest thing about going with baluns is that Seco-Larm has a nice
ground loop isolator that is pretty inexpensive compared to some of the
others, and it doesn't grey out the video as bad as the coax one from Pelco.



 


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