Signal Interference

[visa 0]

Hi there,

 

I have installed 7 Cameras in a shop. Out of 7 3 of the cameras are getting lines across the picture not heavy. There a few meters apart. They were working when I installed them. After a month or so I get this problem. Any help would be greatly appreciated.

 

Thank you

[Harrar 0]

Sounds like it may be a power/ground related problem. Are the three "trouble" cameras powered individually or from a common power supply? Has there been any electrical work done in the shop after this month's time when the problem first appeared? No power cables laying on top of your coax/power lines?

[visa 0]

Sounds like it may be a power/ground related problem. Are the three "trouble" cameras powered individually or from a common power supply? Has there been any electrical work done in the shop after this month's time when the problem first appeared? No power cables laying on top of your coax/power lines?

 

Well, all the camera's power supply is comming from one power source. As far as I know the shop is fully functioning and after our cabling no other work is been carried out, and I do not see any. Just a 42" plasma screen is been fitted. Even that is not on our line of area.

 

All our cables are running inside a plastic casing, Now the shop is fully fitted with plaster celing. so it is very difficult to see any power is crossing our cables inside/Middle of the covered area.

[tweak'e 0]

plasma screen are nasty things for emitting interference. however easily checked by unplugging the power.

 

any pics of the interference?

 

have you tried swapping the cameras around? and also just the leads on the DVR? ie is it faulty cameras or faulty DVR.

also check voltage at the cameras in case power supply has dropped a little bit.

[visa 0]

As you mensioned I have changed the camera & I have done a new cabling to those effected cameras. I do not see any changes. After I saw the plasma screen. I did tell the guys to not to use it. So far they do not use it. Since this issue is a high priority.

 

The shop is running 24/7. Well I saw slight disturbance even before the plasma TV in those cameras.

[jeromephone 6]

What kind of shop ? Are you running 3 phase? Have you tried grounding the case to the DVR. Also there are gound loop devices that you can install inline.

[visa 0]

It is a restaurant. I think he is running in Single phase I have to check this!. I will try to ground the case as you said and give the results.

 

What type of ground loop devices do you suggest?

 

Here my work is to install only the CCTV. If the real problem is with ground looping, or electrical wiring then I have to speak to the owners of the shop.

 

Thank you for the advice

[visa 0]

Just found the shop is having 2 phase on the electricity, I have checked the earth, everything seems to be fine, Even the looping is fine, I have no idea what to do?

[SEANHAWG 1]

Sounds like the cameras went defective.

[visa 0]

As I mentioned before this is a month old installation and I have checked every camera individually, no problem with the cameras at all!

[SEANHAWG 1]

Odd. I'm sure you have already tested to see if its not 3 bad channel ports on your DVR or whatever you are using? Try swapping them around any?

[visa 0]

Yap, I have tried all. All the ports are working. Even I have pluged in the camera with a different power line. No luck