ouija

Hello, Recently I helped to install a 7 camera PTZ systems with a DVR unit on a new gas processing plant being built. Everything was working fine until a few days ago, when they began bringing the majority of the plant's equipment online and now the 4 cameras closest to the "inside" of the plant all have some type of interference happening, where the picture has snow or static happening in it. The plant has gone offline recently and the interference disappered, but once they bring all the equipment back online it comes back. We are using 120v power with passive video baluns to CAT5 unshielded twisted pair to all cameras, but have also tried re-running a camera using 18/2 shielded cable as well, both of which suffer from the same interference. I have tried using ground loop isolators for the video signal with little to no improvement. Recently, I opted for a better model of isolator with noise filters built in and am waiting for them to arrive to test. However, I need to cover my bases in case this doesn't help. My question is if anyone on here has ever experienced any type of interference similar to this and if anyone has any suggestions to solutions or ideas to eliminating this problem. Could is possibly be a "dirty power" issue and would an inline power filter help? something similar to this perhaps? http://www.automationdirect.com/adc/Overview/Catalog/Power_Products_%28Electrical%29/Power_Line_Filters;jsessionid=5e30175972762ee594465b4821315a3d2625?source=google&keyword=EMI%20line%20filter&type=search&gclid=CKL-n4ngv6gCFSYZQgodURXYqQ I've read that these can help eliminate EMI and RFI so I'm hoping they might help. However, I'm worried that something might be directly interfering with the cameras themselves, or would it possibly still be through the video cable itself? Most of the cameras are running about 700ft cable lengths to them, and let me remind you that this is a gas processing plant so there is all type of compressors, pumps, valves, electrical runs, lines, etc. The cables runs with various other cables in outside trays throughout the plant. If anyone has any questions, suggestions or solutions how to remove and troubleshoot interference issues then I am all ears! Any help is GREATLY appreciated!

I've been leaning towards this dirty power interference for some time now. We just tried using active baluns with little improvement, along with a higher quality model of ground loop isolators with built in noise filters and they actually seemed to make the picture worse. They are planning on replacing the cameras with a different model that is less susceptible to interference, with my only hesitation being that if the interference is coming from the power connection(s) then how best should I remove this? Would using a power filter like such do the trick? http://www.automationdirect.com/adc/Overview/Catalog/Power_Products_%28Electrical%29/Power_Line_Filters;jsessionid=5e30175972762ee594465b4821315a3d2625?source=google&keyword=EMI%20line%20filter&type=search&gclid=CKL-n4ngv6gCFSYZQgodURXYqQ

Sorry! I mislead you yet again... grrr... this is a PDF I received from the sales rep for the previous years model; The version we have actually supports 120vac (I'll post a copy of it once I can) There could definitely be some type of motor operating somewhere - how could we avoid this interference? I will ensure it is grounded properly and will keep trying to figure out where the issue might be...

That is a brilliant suggestion! However, this plant is in a remote location and they unfortunately do not have any test monitors on site. I suppose I could try and get one sent out to them.... Very good suggestion however, thank you.... embarrassed I didn't think of it...

Strange, just tested and works for me. Here's a mirror: http://www.megaupload.com/?d=MU2CTNHC

Sorry for all the confusion. I am not directly involved with the wiring of the system being that I do not have clearance to do so on site, so I am simply relaying all the information passed to me by the electricians on site. My understanding is that all 7 cameras are directly connected to 120VAC which all feeds back to the same circuit / panel. There are no a/c adapters or anything being used as far as I am aware. We are using the Ranger - Outdoor 300' Night Vision High Speed PTZ Camera, and the manual can be found here: http://www.mediafire.com/?t9052o1sa6u2pj2 The spec sheet for the CAT5 cable being used can be found here: http://www.mediafire.com/?4e2yp4412oxf6ff The manual for the DVR unit can be found here: http://www.mediafire.com/?wd9hcc5iyp6obc9 Some (rather poor) pictures of the interference seen on the viewing monitor can be found below: http://i.imgur.com/JWtPA.jpg http://i.imgur.com/6hH29.jpg Any thoughts? Update: One of our electricians just informed me that they are using shielded CAT5 now and there is still this interference issue. Providing that the grounding is adequate the shielding itself wouldn't aid this interference somehow would it? I would think it should help... but need to ask

The are all connected to the same circuit and we have tried using a ground loop isolator in case that was the issue and it didn't seem to help; I am going to try using a different unit with a built in noise filter to see if that helps. My brother (a master electrician) seems to think it is an issue with the video runs themselves, possibly because of the unshielded CAT5 getting interference from something. However, I thought using shielded is not recommended for long distances as the shielding can actually cause interference as well (most of the cable runs to each camera are 700ft or more) and so if this is the case would my only option be looking into using fiber optic instead? (providing that using these ground loop isolators on the video runs and power filters on the a/c connections don't help) He was also telling me that the cables should be ran with a 600mm or two foot space between any power cable or wires or have a barrier bonded to a ground between them. We will need to double check our cable runs, but I don't believe the video cable is running along any powered wires. Thanks

Sorry guys, I was mistaken; The cameras are being run on 120v a/c, they have a 3 conductor #12. Could using an inline power filter help this situation any? I am going to attempt using some ground loop isolators with built in filters to see if they make a difference, along with active video baluns instead of these passive ones. Thanks again, and my apologies for the misinformation. These cameras have been wired in by a group of certified electricians that have clearance on site, and I am unfortunately relaying information back to them on what the possible issues might be, so I cannot obtain pictures or stills directly. Yes you can take stills with the DVR but again I am unfortunately not on-site to do so, and do not feel comfortable instructing one of these electricians to do so as they have little experience actually using the DVR unit itself; However they are going send me some photos of the viewing monitor as soon as possible.

I will try and take some pictures of the on-screen interference if possible, however cameras are not allowed on site by client request but I will try and get them to make an exception in this case. Nope. Unfortunately we do not have the clearance to either turn off or on any other equipment in the plant other than anything to do with this camera system. We are certain it is some type of equipment in the plant causing the interference but what it might be is still a bit of a mystery. Yes, it appears to be affecting all 7 of the cameras, however the 4 cameras closest to the plant are the ones that are most affected. Update (from one of our installers): the cameras are being run on 120v a/c, they have a 3 conductor #12. the 12/24 volt is ran on an 18/2 for camera 1 and the others are on the cat5 cable We can CAT5 for the video to 6 of the cameras, and one camera is using 18/2 shielded for the video. Any thoughts?