Problem at night

[Opeth]

Hi there.

I installed an analogue system to my wifes school with 14 hdcvi cameras dahua and xvr5116hs-i3 i wired the system with video power balun pfm802 using utp cat6 and i bought a bare power supply 12v 20 amps. I took 2 plain wires 2.5mm to postive and negative of the power supply and i use two splitter 1in 8 out to connect power to cameras.
The problem is at night i get this bad image with these lines.i measure the voltage to each camera at night and it is 12v. So i dont have voltage drop. I post some videos below to check and the connection idea.

Thank you
View attachment 20220610150541.mp4

 

[bigredfish]

Couple of things.
It can be difficult tracking down what’s causing the rolling lines but here’s a few things to check

Is it happening with all cameras or just certain ones?

• check to see if the cat6 is running parallel to any main power lines (120 or 240v) within 18-24 inches
• I always ran 3 pair for power and 1 pair for video. You might try one like that.
• I never had much luck with a common power supply. I ended up with separate 2amp wall warts for each channel. Yes it makes for a messy install. Try isolating one camera to a separate power supply.
• again if only certain cameras, Check your video wires at the balun to be sure you’re getting good contact.
• if all cameras it could be a ground loop which is difficult to track down

 

[Opeth]

This happen only at night to all cameras. I post an installation pictures. I use video power balun so i had to make rj45.

 

[sebastiantombs]

If the cameras have an "anti flicker" setting in their configuration try using 50hz or 60hz. You may be getting a "beat" between the scan time of the cameras and the "off" time of the lights.

 

[Opeth]

If the cameras have an "anti flicker" setting in their configuration try using 50hz or 60hz. You may be getting a "beat" between the scan time of the cameras and the "off" time of the lights.

Ok i will try tonight. The cameras have anti flicker and it set by default to outdoor. Before check this is it matter if it pal or ntsc for the anti flicker config?

 

[Opeth]

And what it happen is if i choosè pal i have the lines during day and night if i choose ntsc the lines disappear at day and only at night i have the problem

 

[DsineR]

Test if a power issue by disconnecting one cam and install a temp dedicated power supply - still get lines at night?
Since this is only a night issue, check if disabling / enabling the IR light at makes a difference. A power conditioner at the power supply may resolve this.
The 50hz/60hz is also a good option to try, which also changes the frame rate. May help eliminate a 'dirty power' issue at 60Hz.

 

[garycrist]

New LEDs will cause a roll. I can not see the videos here. I think it is the duty
cycle of the LEDs cycling I can see it on a 5842 (?) at night too.

 

[looney2ns]

As @sebastiantombs suggested above, plus adjusting the shutter speed of the camera can sometimes help as well.

 

[Opeth]

Just wondering. I see now live the cameras and i dont see any line but when i go back to playback i see them is it anything had to do with playback?