CCTV System Damanged Twice By Surge?

We installed a basic analog CCTV system in a residential property roughly 2 years ago. The system was a simple as you can get:

  • DVR with 12 volt plug in power supply
  • 4 Analog Cameras connected with rg59 video and 18/2 power
  • 5 amp power supply with 1 to 4 pigtail to power cameras
  • 40 ft of Cat5e to router
  • 50 ft of vga cord to TV

After about a 9 months of service we had a service call. The DVR powered on but it did not have any form of video output. No Hdmi, vga or bnc. We replaced the DVR under warranty. I suspected a power surge.

We just received service call 2 years after install and we found the following. DVR powers up but no video on hdmi, vga or bnc. All four cameras are dead. No video output.

Both the DVR and Camera power supply's still work supply 12V

On both service calls nothing else in the home has been damaged by surge. What is the likely cause of this. Will installing surge protectors at DVR and inline protection for cameras help?

Just looking for some ideas of what I might be dealing with. Not sure if it matters but the DVR and cameras were IC Realtime (Dahau).

Thanks for any input.

Might consider lightning damage. You might check in the attic and verify if there is an existing antenna that is not grounded too.

Verify that the water meter is by passed with a ground strap.

Cameras are Analog with 12v Siamese cabling?
CAT5 with Power Video Balun?
Power supply for each camera? or a DC splitter for cameras, separate for NVR?
Cameras mounted on aluminum eaves?
AC Neutral to ground < .25 volts?
AC service outdoor earth rods are notorious for being shielded from rain or near a deck, resulting in very dry soil at ground. But other things are ok.

Nearby earth strikes can find the cameras and get back to earth via the NVR and/OR PS....
transient surges...... Seen them smoke modems, via telephone lines, cable modems, etc....
Battery Backups and surge protection (with proper grounding) is best thing to stop these....

If you can see burnt components on the PCB in the DVR, see if you can follow a trail of damaged components. If it leads to one of the camera inputs, you'll know that a surge from that camera was to blame.

You may wish to consider using a UPS to protect the power supplies for the DVR and cameras. If the UPS dies, it would suggest a surge from the mains power. Good luck!

It seems unlikely that a power surge would affect only the DVR, twice.

What you describe sounds more like lighting/static damage. Or possibly a ground loop issue causing a surge current.

Thanks for the input. I'll post an update once I know the culprit.

Do you know the max amp draw on those cameras? Those cheap 5A bricks are usually pretty lousy quality compared to a cabinet style PSU. Also, when using a 1 to 4 style splitter pigtail, you essentially have no protection between cameras. One gets hit and all will suffer. Not that the cabinet PSU is the holy grail, but at least there are independent outputs per camera.

So, if you had a short in one line or camera, it may affect others. Also, if you had a similar, cheap PSU brick for the DVR, it could have been an issue as well. I know from past experience with some Dahua DVRs, we received under-powered wall wart style PSUs for a short time that just couldn't supply enough power for reliable operation.

Does your DVR had a ground (third pin) on it's power cord? Guess what gaved the path to a lightning discharge true an exterior camera in absence of a proper lightning rod.