Please HELP! In over my head

[DailianInCCTV 0]

Okay, so I'm not completely ignorant to Surveillance systems or networks, but this system is baffling me!

I took on a new job recently after losing my technology firm to employee embezzlement, and this job was for an IT Department at a Hotel, this hotel used to have an excellent CCTV system and server, but that was years ago, and there has not been an IT department since, they've had basic caveman maintenance guys running the show since.

the system needs a massive amount of work done on it currently, however, they have one camera they desperately want me to have working, and that's their Presidential Suites hallway cameras for the 1-5th floors.

All floors but floor 3 are operational currently. However, it appears that they're exhibiting poor quality video signal (some aren't displaying color very well, like the Tone has been turned up and the color screen and contrast reduced), and most of the cameras are displaying what appears to be a ground loop (due to me seeing vertical black bars that travel from right to left on each individual display).

 

There are four cameras that are displaying virtually no image whatsoever! it is a very faint digital line scramble that comes through intermittently, but otherwise is showing a black screen. However, the DVR does in fact acknowledge that it is receiving a signal from the camera!

 

My belief is that there is a ground loop in the data lines somewhere (the system has over 100 cameras in the hotel, my largest setup prior to this was a paltry 24 cameras, but since I was the installer, I know it was done with the utmost care and quality).

I'm used to using 24 VAC cameras, but these are all 12 VDC cameras. They are powered via Wall Warts, and the Wall Warts are connected to the individual cameras via spliced CAT5 lines. Spliced CAT5 lines are also running the data stream through Video Baluns (the cameras are BNC systems, the Power and Data Lines are run to Baluns and are spliced onto the Ethernet system. The Power cords are spliced using Small wire pinch splicers onto the proprietary power connector, which is then simply plugged into the camera - for warranty purposes we don't want to damage the existing cameras power or data lines to just splice them directly onto the CAT5 cables.)

 

I have never really used a Multimeter before, but I have traced the lines using a Tone Generator and Probe, and have verified with that the toner that the data line reaches soundly from camera all the way to active DVR receiver.

Can anyone provide links or explain to me how to properly test both the data systems and the power systems to ensure that the DC power levels are within proper limits? How does one properly determine that it is in fact a ground fault and not some other problem? (I see ghosting from one camera to another, so I know Crosstalk is occuring too, however, this doesn't seem to be a problem for the current management, at least not imperative to repair right away, the primary concern is establishing connectivity to the lost cameras, and determining what is causing the system to drop off repeatedly?)

 

Side note: apparently one mission critical Camera was repaired before by someone from Maintenance that had almost no experience in CCTV or IT, and it was working for all of 29 hours before going offline and not continuing to function.

 

What troubleshooting tips does anyone have for me? How do I test the cameras? (I've tried Swapping the cameras, re-doing the splicers, checking the baluns for failure by using known good ones, I've ran the Line Toner to ensure that the connection is functioning, but I also read something about looking for Ground Loop in the data line - something that can happen with 12 VDC cameras easily - by testing the Data Line against ground and looking for some very small discrepancies.).

 

Thankfully the employer is being patient with me because of the sheer amount of damage that has been caused to the system by the cavemen in maintenance over the years, they've installed cameras with improper hardware (framing screws, etc. I am curious in a building with metal studs, can a framing screw going through the mounting hole of a 12 VDC camera cause it to effectively ground out against the Metal stud and degrade/eliminate picture?)

 

I apologize for the massive post, and really would appreciate any help that can be offered to me!

[SyconsciousAu 0]

 

I apologize for the massive post, and really would appreciate any help that can be offered to me!

 

Start with the basics.

 

With anything electrical the first question to ask is do I have power to the circuit.

 

Buy a multi meter and confirm that you are actually getting the advertised voltage and current from your power packs and that the power that is arriving at the camera is sufficient in both voltage and current.

 

After confirming you have power I would get a test monitor and confirm that you have a video signal at the camera.

 

If that checks out then move on to the DVR.

 

At the DVR connect the suspect camera to an input that is known to be working. If you suddenly get video from that camera your input at the DVR is the issue.

 

With all of those things eliminated then go looking at the signal path between the camera and the DVR.

[fertilebert 0]

Are you seriously saying you are an experienced installer , yet you dont have or know how to use a dmm .

[Boogieman 1]

Are you seriously saying you are an experienced installer , yet you dont have or know how to use a dmm .

Did you even read his post? He never said he was an experienced installer!

[fertilebert 0]

Op states he did a 24 camera install that was spot on ?

Which isn't a diy job is it?

So you really did a 24 cam job without a meter ?

Mmmm.

[cornz 0]

Personally i would use a colour bar generator at the camera end and test it at the DVR end.

Long process but will positively indicate the signal strength and integrity....