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Why do these look like this?

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Ok, so I have a dealer of mine installing 16 of our 540VD camera:

http://www.icrealtime.com/solutions/icr540vd.html

He is using the ALTV1224C power supply and all his video cable runs are through cat5e using some Panasonic passive video balun. My questions are where are these diagonal lines coming from and why do these cams look like this. His runs are between 100ft-600ft. I personally think its the cat5 runs using the baluns...but I don’t know. Any thoughts?

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ground loop.............power line interferance..................

 

is the mounting surface metal?

Are the cams grounded?

are the cams in another building from the DVR?

are all cams effected?

 

ground loop; make sure the power supply is plugged into the same strip as the DVR. make sure camera's are not grounded seperately.............do not fround them. do you have a CM2? (camera master 2) if yes you can verify the GL via test.

 

isolate and trace; isolate (1) really bad pic/camera from the power supply and DVR.........view on monitor at end of CAT5. results will give you a hint as to ytour problem.

 

one camera maybe causing bad pics on all via noise. isolate one camera at a time to ensure good.

 

bottom line is you are getting "noise" on your video...finding that source takes a bit of selective troubleshooting but you'll get it. one camera cable could be installed ontop of a AC line which is passing that interferance back into the system?

 

what type of CAT5 is it?

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They are not mounted to metal.

 

As far as them being grounded, would this need to be done at the power box?

 

The dealer is checking now for any cable runs over AC lines.

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I had a similar problem on one of my installs last month. We replaced everything, tried different power supplies 12 and 24, pulled new twisted pair, etc. We ended up replacing the twisted pair with rg-59 (as it was suggested by forum members) and the image improved to perfect. Don't know why... just that it worked.

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I've also seen that before with coax,, it's not ground loop. I've always thought them to be 60hz lines from AC interference. It can also be a bad connector.

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I have that with a bad connector on the tv sometimes - exactly the same lines, wiggle the connector, it goes away.

 

Will have to fix it sometime

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I just wanted to share my experience. I had one camera out of 16 display the same lines. I checked and wiggled the connecter at the DVR and there was no change. I then removed and somewhat cleaned the connector at the camera and the lines went away. I should add that I used RG59 cable.

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that looks like a video cable issue .. change the baluns and should be good to go .. you get that when you run cameras on telco or cat5 without baluns ... so probably bad baluns or they only go so far ... course could be power related also but since they are using cat5 id check that as well.

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first of check for ground lopp as stated. Tell them to power down the whole system dvr and cameras and make sure the cable is connected at either the camera end or the dvr end. Then get a multimeter and measure for low voltage ac. anything over 1.0v can cause problems. but not usually lines that look like that. Could be interference.

ask them if they are using are using a ups on any part of the system. If so replace the ups from one that has a square waveform to one with a sine wave form output.

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i dont know they for some reason dont state anything about what waveform it outputs. As a general rule of thumb if it does not state that it is a true waveform output then it is probably a sqaure waveform. But i could not find anything on their website about output. I would call them and ask them specifically.

 

here is short help full link.

 

http://www.minutemanups.com/support/pwr_un10.php

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Hi rory, found a bit info on it,

 

http://sturgeon.apcc.com/techref.nsf/partnum/990-2129/$FILE/990-2129-EN.pdf

 

According to that (last page) its a step approximated sine wave, otherwise known as a simulated sine wave, step approximated sine wave and many other names.

 

Its not a pure sine, but not a straight square wave, its a square approximation of a sine wave, so it goes up and down in blocks, like a sine wave, but not as smoothly as a pure sine wave.

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Andrew,

 

I have seen that when the camera is not getting all the mA of power that it needs.. Check the power adatpor or the power box.

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I've seen this before using cat5 12vdc cameras and a DVR, what has worked for me in the past is to power the cameras from individual "wall warts" rather than all sharing the same power source. You may not have to power them all seperately, sometimes just removing two or three will resolve the problem, or try a couple of power supplies and group the cameras according to the length of the cable run, keep the short runs on one supply and the longer runs on another power supply

 

Doug

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Thank you all for the insight. I havn't heard from my dealer today. So, either he figured it out or gave up

 

I am thinking the baluns and utp are causing the issues. He does have one camera using siamese and there are no lines but, the video still looks not right.

 

Oh, and if I didnt mention the DVR is a DM DS2.

 

Thanks,

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Yeah im getting something even stranger than that .. no lines in the image at all .. but at night with the IR .. when I play it back and speed up the playback I can see waves going up and down .. strange .. anyone seen those before?

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Here is what I have seen in the past, its not so much that the power supply can't provide enough power, nor that the cable runs are so long that there is excessive voltage drop, but rather there is some sort of interference between the power and the video and/or ground when powering multiple 12 VDC cameras from the same source. My experience has been that it occurs more when the cable runs are of greatly differing lengths. I believe it has something to do with the video ground and negative being common at the camera, but at the head end the video ground is probably tied to the chassis of the DVR and then to an electrical ground, while the power negatives are all common, but floating with respect to ground. I can't say for sure that separating the camera power supplies will work in this case, but I have run across this at least a dozen times when using UTP and multiple 12 volt cameras, and separating the power and/or grouping the power has resolved it in every case. Using a quality active balun at the head end will probably also resolve it, but that's a more expensive solution. At some point the dealer is going to have to try something if he wants to resolve the problem, he may as well start with something that will cost little in parts and very little labour. It would take less than an hour to try this, just remove all the cameras both positive and negative from the power supply and connect one up, if the picture is still bad then you know that isn't the problem, if the picture is clear then keep adding cameras until the problem occurs, my guess is that most of the cameras can be left on the Altronix and maybe 3 or 4 will end up on individual wall warts, or a second PSU.

 

If it resolves the problem, all well and good, if it doesn't he can move on and try something else.

 

Doug

 

 

 

I dont think its the power. He is running 18-2 for his power runs. Here is the box. http://altronix.com/index.php?pid=2&model_num=ALTV1224C

It is rated at 437.5ma per channel. The cameras only need 150ma at most.

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