Slight Distortion in Video Feed

[MasterVision_Tech 0]

Hey everyone,

Thanks for taking the time to read this and help me figure this out. I just wanted some other opinions on what the problem might be, so don't be afraid to speak up !

 

Project: 5 Parking Lot Camera

Cams : Eclipse ECL-640

Power: 24V Power Supply 1 AMP

Wiring - Video Balun (passive)

(One 4 port and One single) using CAT5 for about 300'-350' --> Then to RG59. Longest run on RG59 is about 300' additional feet. Power is being run over the RG59 so longest run there is also 300' to camera.

 

Problem: When I go inside to look at the DVR feed, I show faint lines running across the screen. It shows this way for four cameras. If I add the fifth camera line in, the picture gets very distorted (mostly likely because of an improper wiring job but another tech ran the line). 120V had to be supplied to the site and the electricans came out to do the job.

 

I can tell you that the power board for the cameras, has not been grounded. I have a feeling that that would make a difference on a AC setup, but there was no where to ground the wire onto the board. When I make my return trip, that was one of the things I was going to try to see if that would fix the problem.

 

The cameras are mounted to fiberglass poles (I can be sure of this because most of the dust particles are still in my arms) using a pole mount kit and metal screws.

 

I guess what I am asking is:

 

Do you believe that the power box should be ground and do you think that is the issue ? Where would you mount it ?

 

Personally, I do not believe that it is the baluns. Four cameras are running on one line and the last camera is running on the second line.

 

I have been reading about the ground loop effect, but I don't see where else I could be getting the problem except maybe at the power box. I don't believe that the camera mounts or locations is fault either. Like I was saying before, I'm usually a DC person but the runs were to long for me to run DC. Let me know what you think

[Soundy 1]

Your description of the problem SOUNDS like a ground loop problem... can you provide some screenshots of the interference, both with and without the fifth camera?

 

If I follow the description, you have Cat5 from each camera back to a balun, then coax from there back to the DVR? Power is running via coax to the baluns, then splitting out and running over the Cat5 to each camera? Or one Cat5 from the DVR to the four-port balun, then coax from there to the camera?

 

Silly question, but I assume you have baluns at both ends of the Cat5 runs?

[rory 0]

When you view the camera at the DVR end direct to a monitor and not on the DVR, how is it?

When you view the camera directly at the camera on same power, how is it?

When you view the camera directly at the camera on separate localized power, how is it?

Have you tried checking the video where it splits off to the RG59?

 

As mentioned could be ground loop, but could also be other things like just a bad video connection/splice, even a bad camera. Could also be the balun or how you are powering it?

 

What RG59 cable are you using? And is it siamese?

[MasterVision_Tech 0]

1.When you view the camera at the DVR end direct to a monitor and not on the DVR, how is it?

2.When you view the camera directly at the camera on same power, how is it?

3.When you view the camera directly at the camera on separate localized power, how is it?

4.Have you tried checking the video where it splits off to the RG59?

 

As mentioned could be ground loop, but could also be other things like just a bad video connection/splice, even a bad camera. Could also be the balun or how you are powering it?

 

What RG59 cable are you using? And is it siamese?

 

1. I have a test monitor that I was checking the cameras with but when I plug into the video feed, the cameras look fine. Granted my test screen isn't an LCD but it does the job.

 

2. Same thing. When I plug in directly in the back of the camera, I don't see any of the distortion. I had one of my techs sit inside at the DVR and let me know if he sees anything. He told me he still did.

 

3. Im going to try to get back out there today with a DC power supply to see if that has anything to do with it. I was thinking that it was the power supply because I have not had these problems and this was the first time that I used the AC power supply.

 

4. I took my test monitor over to where the video feed was, but once again my test display does not show me anything that clear.

 

I may have to find another screen to use to be able to see the distortion and find the problem. My siamese cable is from sewell direct. Ive ordered from them in the past and that make some pretty good products.

[MasterVision_Tech 0]

Your description of the problem SOUNDS like a ground loop problem... can you provide some screenshots of the interference, both with and without the fifth camera?

 

If I follow the description, you have Cat5 from each camera back to a balun, then coax from there back to the DVR? Power is running via coax to the baluns, then splitting out and running over the Cat5 to each camera? Or one Cat5 from the DVR to the four-port balun, then coax from there to the camera?

 

Silly question, but I assume you have baluns at both ends of the Cat5 runs?

 

Im going to try to get back out to the site today to see if I can get some pictures. I would have taken them yesterday, but I was a little to tired. I will post them up today if I can.

 

 

The layout you have is a little wrong. I try to explain it better....sorry.

 

From the camera, the video is connected using siamese cable down the line to the power supply and video balun (max distance from camera to power supply and balun equipment about 275' - 300').

 

The power supply and video balun are in seperate units. Video is being transmitted back inside the warehouse and to the office using CAT5. Video balun are at both ends of the CAT5 cable. I would say the distance on the CAT5 is around 300' - 400' feet also.

 

I am using two CAT5 cables to send the signal back from the cameras. One of the CAT5 cables is sending the signal back for four of the cameras, and the second CAT5 is being used to send the video back for one of the cameras. All cameras are showing the distortion. Video baluns at both ends.

[bpzle 0]

Ground loop?! On AC?! You guys are crazy! lol

 

Do you have a volt meter? Check the voltage at the camera.

 

Running multiple types of cable for each camera is a headache waiting to happen! Don't do it again! It will only confuse you when it comes time to troubleshoot.

 

So, if voltage is good under a load... Try using a totally different make/model camera temporarily to see if you still get the lines.

 

I'm betting that the problem will go away when you use a different camera. How do I know? I've used several 640s and had this same problem on ALL of them. Some worse than others. I won't use these cameras anymore.

 

However, it's good to cover your bases before you send back to Eclipse and eat 3 percent plus shipping to return. Hope you saved the boxes! I have a hard time throwing away boxes, even a month or 2 after an install. lol

Edited September 4, 2010 by Guest

[MasterVision_Tech 0]

Do you have a volt meter? Check the voltage at the camera.

 

Running multiple types of cable for each camera is a headache waiting to happen! Don't do it again! It will only confuse you when it comes time to troubleshoot.

 

So, if voltage is good under a load... Try using a totally different make/model camera temporarily to see if you still get the lines.

 

I'm betting that the problem will go away when you use a different camera. How do I know? I've used several 640s and had this same problem on ALL of them. Some worse than others. I won't use these cameras anymore.

 

However, it's good to cover your bases before you send back to Eclipse and eat 3 percent plus shipping to return. Hope you saved the boxes! I have a hard time throwing away boxes, even a month or 2 after an install. lol

 

I will also check the voltage on the camers when I go back out today. I have some toshibas that I can throw up to see how they look.

 

Im sorry you had problems with the 640 but I hope that is not the case with these cameras ! I already threw away the boxes.....don't ask why I just did not think I would need them. lol I think the heat was just getting to me yesterday.

 

I'm getting read to head out there in a little bit to test the connections and take pictures of the distortion. I will bring back my findings.

[jeromephone 6]

I am a bit confused as to why you would run this combo of cable.

 

If you run cat5 with baluns and a seperate power wire it should make things simpler. We try to look a job and think about how are we going to trubleshoot this in three years. A different tech goes to the site should not have to spend time figuring out what the heck these four kinds of wire are. We tend to overkill the power wire a bit and I like isolated power supplies when possible. I also figure if we are going to warrentee this install I don't want to go back and redo stuff with the costs coming out of my pocket.

[rory 0]

The layout you have is a little wrong. I try to explain it better....sorry.

 

From the camera, the video is connected using siamese cable down the line to the power supply and video balun (max distance from camera to power supply and balun equipment about 275' - 300').

 

The power supply and video balun are in seperate units. Video is being transmitted back inside the warehouse and to the office using CAT5. Video balun are at both ends of the CAT5 cable. I would say the distance on the CAT5 is around 300' - 400' feet also.

 

I am using two CAT5 cables to send the signal back from the cameras. One of the CAT5 cables is sending the signal back for four of the cameras, and the second CAT5 is being used to send the video back for one of the cameras. All cameras are showing the distortion. Video baluns at both ends.

 

Did you try one camera connected at a time on the DVR?

And one camera powered up at a time?

Also going by the specs of that camera it is 12VDC @ 850mA?

You say you are using a 24VAC power supply?

12VDC probably wont make that long run either.

[bpzle 0]

That camera is dual voltage.

 

When we had issues with them we tried AC and DC voltage, with the same results.

[Soundy 1]

I don't think a DC power supply will help - simply having AC power does not cause noise or interference. Where you normally see a problem is with cheap 12VDC cameras that have a shared ground between power and video; then you can easily get ground loops. 24VAC and dual-voltage cameras don't typically suffer from these types of ground loops because the power and video grounds are isolated by the internal power supplies.

 

In fact, voltage SHOULD NOT be your problem here - if the camera will run on 12VDC, it should also work with 12VAC, so it would be almost impossible to see enough voltage drop to be a problem at 24VAC, especially over a mere 300' of 18/2. By my calculations, you'll see about 3.5-4V loss at 12V/0.85A draw... so 12V would definitely fail here. 24VAC/.4A draw would be only 2V drop.

 

The symptoms you describe really sound like a ground loop though, especially since they get worse when you connect the fifth camera. This could happen if the cameras themselves are grounded at their mounting points, and the DVR is grounded to a power earth ground. Try using a ground-lift on the DVR (or snip the ground prong off its power cord), or try un-mounting all the cameras temporarily (hang them with a piece of string, or if they're light, let them dangle by the wires, anything so they're not physically touching anything.

[bpzle 0]

K.I.S.S.!

 

 

I'm telling you, it's the cameras. I've seen this before.

 

Ground loop can happen, but it's been my experience (10 years or so) that it's extreamly rare. I don't think I've ever seen it on AC powered cameras...

 

But either way, I've used these cameras before and I'm telling you, IT'S THE CAMERAS!

[Soundy 1]

Or hey, you know what, it could be the cameras, too!

[bpzle 0]

Lol!

 

Let's start taking bets... Loser has to use twist on BNCs on their next job from start to finish AND take pictures in front of a newspaper to prove it! hahhaah

[rory 0]

yeah try another camera and see what gives.

I had something similar these past couple weeks that had me pulling my hair out, with a couple old EX82s .. worked by me with no lines .. I even spent hours in the middle of the night gutting them and taking the camera modules and lenses to pieces (never again!) but they worked fine and changed some parts from other used cameras that had some good parts, put them back at the client just sitting on the grass or ladder or even in someones hand.. lines .. another camera on the same pole .. no lines. .. another camera from another location on the same pole and same cable .. no lines .. i changed the power board on the camera module but still lines at the client location ... bad camera .. but ONLY the color camera module .. it also has a BW camera module .. both modules have the camera board then a power board together. There were a few different versions of the cameras though .. purchased at different times, design was a little different among them. I had to change the entire color camera module for the same reason just a few months ago in one of the other cameras ..and oh yeah all 24VAC. But this time I had no good color camera modules lying around .. so had to buy a couple new cameras. One was 9 years old anyway, the other was about 4 years old.

[MasterVision_Tech 0]

I am a bit confused as to why you would run this combo of cable.

 

If you run cat5 with baluns and a seperate power wire it should make things simpler. We try to look a job and think about how are we going to trubleshoot this in three years. A different tech goes to the site should not have to spend time figuring out what the heck these four kinds of wire are. We tend to overkill the power wire a bit and I like isolated power supplies when possible. I also figure if we are going to warrentee this install I don't want to go back and redo stuff with the costs coming out of my pocket.

 

If I were to run a single siamese cable to each individual camera, my max run would have been close to 700ft total. It was my original intention to run that length but I did not want to have problems with the video signal later on. The setup is not complicated and I am sure that a tech with a little common sense would be able to figure out the wiring. If not, there are labels on all of the wiring that I did and that at least should make it a bit easier.

 

 

 

This is just an outline of the site to make things easier to understand. I did not get a chance to go out to the site. They were doing upgrade and only were available for half the day. The video degrades on the DVR side and not coming in from the cameras.

 

I did take some pictures and I will upload them here in a bit.

[tomcctv 187]

Hi.mastervision.

 

looking at your pic. you have all cameras going to a power supply which you have listed as 24v 1 amp. if that is the case then you have no chance running all 5 cameras off that. you will need that for each camera. the cameras you have listed are 950ma with ir.

[MasterVision_Tech 0]

Hi.mastervision.

 

looking at your pic. you have all cameras going to a power supply which you have listed as 24v 1 amp. if that is the case then you have no chance running all 5 cameras off that. you will need that for each camera. the cameras you have listed are 950ma with ir.

 

My mistake... 8 OUTPUT 24VAC 4.2AMP

[bpzle 0]

that power supply isn't big enough! you're maxing it out.

 

That's a problem, but I don't think its THE problem. I still think its the cameras.

[MasterVision_Tech 0]

that power supply isn't big enough! you're maxing it out.

 

That's a problem, but I don't think its THE problem. I still think its the cameras.

 

Think so? When I look at the video feed at the cameras, I don't see the distortion. The only other thing that comes to mind is that when I was at the site yesterday, I noticed that one of my techs ran the CAT5 line right next to a 480v conduit.... The conduit runs to a 480v sub panel that they use for their forklift chargers..idk may have something there.

 

I forgot who asked or suggested, but there is no grounding for the DVR plug and the cameras are mounted to fiberglass poles so I don't believe that there would be any interference there...

[Harrar 0]

The only other thing that comes to mind is that when I was at the site yesterday, I noticed that one of my techs ran the CAT5 line right next to a 480v conduit.... The conduit runs to a 480v sub panel that they use for their forklift chargers..idk may have something there.

 

If the CAT5 is running parallel along the 480 volt line you may have found a good cause for your distortion problems.

[bpzle 0]

Definetley! That's a very big no-no!

[Soundy 1]

that power supply isn't big enough! you're maxing it out.

If that current rating on the cameras is 950mA @ 12VDC, it's going to be only half that at 24V.

 

The only other thing that comes to mind is that when I was at the site yesterday, I noticed that one of my techs ran the CAT5 line right next to a 480v conduit....

Yeah, I'm thinking that'll do it, too... CROSSING or PASSING near a line like that wouldn't be a problem, especially the way the balanced line inherently rejects noise, but running it anywhere close to the line for any substantial distance will induce HUGE amounts of noise. I bet if you watch the cameras, you'll see they get worse as they plug in more forklifts to charge, too, as the current draw on the 480V line will get higher and thus create stronger fields around the conduit.

 

Of course, it could just be the cameras, too

 

I am a bit confused as to why you would run this combo of cable.

Actually, I've done similar in just such a situation as well. You might do it if you couldn't get a large number of coax drops from one point to another - you can easily get two Cat5 through 1/2" EMT, whereas you wouldn't get 5+ RG59 through even 3/4" EMT (especially not if there's more than one or two bends, and not without LOTS of lube). You might do it if the Cat5 was already in place, too. Nothing wrong with this sort of topology.

[rory 0]

If I were to run a single siamese cable to each individual camera, my max run would have been close to 700ft total. It was my original intention to run that length but I did not want to have problems with the video signal later on.

 

Yeah but running cat5 with passive baluns is not helping either.

At that distance I would not hesitate to go active to passive.

[MasterVision_Tech 0]

If I were to run a single siamese cable to each individual camera, my max run would have been close to 700ft total. It was my original intention to run that length but I did not want to have problems with the video signal later on.

 

Yeah but running cat5 with passive baluns is not helping either.

At that distance I would not hesitate to go active to passive.

 

That was my second thought was to switch over to active..but you wouldn't use active at both ends? I figured that the passive baluns would at least cover 350'ft .

 

So on Tuesday, I plan on switching the CAT5 over from running along the 480v conduit and then switch the baluns if that doesn't work.

 

.....and HOPEFULLY it isn't the cameras

 

 

EDIT: Pics

 

 

 

Length of warehouse were CAT5 was run

 

 

The silver conduit to the left of the fan is where my tech ran some of the wire against.

 

 

Charging station on other side of the warehouse

 

 

View from one of the cameras (pic taken on my phone, not from camera). Power box is located in the corner by my black truck

 

 

 

Outside power box. Power box is bottom left light colored box...Video is small box on ground ( it is raised off the ground)

 

 

 

DVR location - Maybe interference from Switches or Equipment ?

Edited September 5, 2010 by Guest