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Possible voltage drop / CCTV over cat 6 - VLOSS

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Hi everyone, i am not an expert and don't pretend to be so please bare with me

 

I installed a 32 camera system and have an issue with a few cameras that are dropping..

 

i can see there is power to the camera as either the IR is lit or if i put my finger over the sensor the IR comes on, however at the DVR end it shows that there is a VLOSS

 

each camera is connected with baluns either end of cat 6 cable.

 

i am using 5amp PSU with a 4 splitter to power 4 cameras off one PSU

 

the cameras have power of 300MA so having 4 cameras to a 5amp PSU should be plenty

 

the cable length might be a factor because the longer the distance the more voltage drop however one of the cameras was not a big distance , less than 10m. i checked the cable and it came back fine. so i replaced the cable to be on the safe side just to test and although the camera came back online it was VLOSS the next day, or when i checked again

 

this is happening with 3 of my cameras with various distances, one is about 10m away, the other two are probably about 30m. no way are they greater than 50m which is not supposed to be an issue either.

 

Someone said that it might not be getting enough power when the IR comes on and this is when it loses video

 

they suggested i try and use the PSU for 2 cameras instead of 4 however i would of thought 5amp would of been plenty to handle 4 cameras or could it be that longer distance cables draw more from the PSU itself and it cannot pass enough to X camera?

 

not entirely sure how this voltage drop works and if the scenario above is plausable?

 

anyone else come across this and how did you combat it?

 

i cannot run any power locally to the cameras but i do have spare 12v PSU's to try and i could run them independant on each camera to test

 

could i get a 24v and convert back to 12v if needs be to give more power so less voltage drop?

 

again i am not to clued up on voltage and this issue

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Hi everyone, i am not an expert and don't pretend to be so please bare with me

 

each camera is connected with baluns either end of cat 6 cable.

 

i am using 5amp PSU with a 4 splitter to power 4 cameras off one PSU

 

Someone said that it might not be getting enough power when the IR comes on and this is when it loses video

 

they suggested i try and use the PSU for 2 cameras instead of 4 however i would of thought 5amp would of been plenty to handle 4 cameras or could it be that longer distance cables draw more from the PSU itself and it cannot pass enough to X camera?

 

 

First off, no, I wlll not "bare" with you...I hardly know you.

 

There could be a few things going on. Have you measured the voltage at both ends of the run(s)?

 

What baluns are you using?

 

Can you double-up two pairs on one CAT6 for the power? You can only push so much water through a hose. Electricity = water, wire = hose.

 

I did have a similar issue once (not with baluns, though) and the solution was to switch to a heavier gauge wire.

 

I would start with testing the voltage (load & no-load, IR on/IR off) on both ends. Let us know what you find.

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Hi guys

 

I have not done that yet, not sure how I can do that with the cable and baluns i have

 

I am using cat 6 cable and have baluns at either end. From the dvr end I have a 5amp psu which has a splitter on to feed 4 cameras.

 

The cat 6 cable terminates either end into an rj45 plug and I am using balun king (baluns)

 

The cameras I am using are rated 300ma

 

The 3 cameras I currently have an issue with are approx 25m in length

 

I have tested the cameras with it's own psu albeit from the dvr end so it is still passing power through balun and cat 6 to the camera, and I get the same problem

 

I have had the cameras working for hours at a time but will goto video loss, also the dvr still detects a signal as if I unplug it, it will alarm although it does not do this all the time, but I have noticed it

 

One of the cameras went blank but did not report video loss however it has given video loss in the past

 

I have also noticed that if I unplug the cat 6 cable from the balin at the dvr end it sometimes brings the video back but will soon vloss

 

I have also noticed that the IR will still work on the cameras but it gives a vloss at the dvr

 

Thanks

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I have not done that yet, not sure how I can do that with the cable and baluns i have

 

The cat 6 cable terminates either end into an rj45 plug and I am using balun king (baluns)

 

 

We heard you the first time. No need to repeat your issue.

 

A) Check for voltage loss. Do that first. You check voltage loss just as you would with any other wire.

 

B) Balung King?!? 183940_1.gifGet real baluns (e.g. Nitek, NVT)

Edited by Guest

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You asked if I could double power, how can I do that with rj45 plugs and one single cable hence repeating my setup

 

Would I test the end of the rj45 plug for the voltage?

 

Thanks for your help

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You asked if I could double power, how can I do that with rj45 plugs and one single cable hence repeating my setup

 

Would I test the end of the rj45 plug for the voltage?

 

Thanks for your help

 

If you're using RJ45 plugs, then that would be tough to double-up. Most professional baluns use pressure-activated wire retainers which would allow for doubling-up.

 

You can test the end of the RJ45 plug for voltage if you have some tiny probes (and good eyesight). The rest of us would probably use a breakout box or banjo.

 

183945_1.jpg

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finally got around to testing one of the locations/cameras

 

i tested the voltage at the end of the balun, camera end and it was 12v. so no issue with power

 

i swapped the camera with one working location and low and behold the working location became the vloss and the trouble location is now working

 

so must be the camera that is the issue?

 

also i have two others to swap/test which have the same problem..

 

so looks like i might have 3 duff cameras..

 

will test/swap the others when i get a chance

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You asked if I could double power, how can I do that with rj45 plugs and one single cable hence repeating my setup

 

Would I test the end of the rj45 plug for the voltage?

 

Thanks for your help

Almost all baluns that provide you an RJ45 jack are already doubling or tripling the power pairs, so that's not your problem. 300mA over even single pair should be fine at a mere 20-30m. Anyway, you've already measured power at the camera end and found it sufficient, so voltage loss obviously isn't the issue. To completely rule out power loss, try powering one or two of the troublesome cameras directly (run an extension cord if necessary) and see if the problem persists.

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