Dahua HFW-3200C blinking night vision problem

[gaijin4ever]

Dahua HFW-3200C blinking night vision problem - SOLVED

We have 6 of these cameras, bought over the course of a year. They all have the current firmware.

It started with just one, but now 3 of the six have the same problem with the night vision. It blinks. Sometimes it's worse than others, and after the dusk changeover, the blinking can stop anywhere from 3 to 6 hours after dark, but it can also blink all night on some cameras with the issue. I went outside and you can actually see the IR going bright and dim on the front of the affected cameras at night.

I thought maybe it was the PoE switch I was using (ES-1100-16P), so I changed to a managed Cisco PoE switch, which also gave me the ability to see the power draw on each camera in real time. The cameras with the blinking are drawing about 1 watt less than the ones that aren't, but all three blinking ones are slightly different power draws.

I've googled this repeatedly as more cameras have become affected, but nothing seems to come up. Has this happened to anyone else? Any idea how to fix this? It's driving me nuts.

 

[ex123yz]

I'm having the same problem with the same camera model.
I didn't come up with a fix for it, and so just using it as Day mode until get a replacement camera.

 

[gaijin4ever]

It's weird that there's NO information I could find about the problem with multiple types of google searches when 50% of my cameras now have the issue. It's good that I at least know SOMEONE else in the world is having the issue.

Now to just find a solution...

 

[ex123yz]

The following post has some discussion regarding IR issue, but no solution over there either.
http://www.cctvforum.com/viewtopic.php?f=19&t=40333

 

[gaijin4ever]

Well, that's some good reading about the issue. Too bad no solutions. I wish someone would have it narrowed down to a bad IR sensor or a bad or overheating component so there was a repair solution. I got these ones straight from China so it will be a pain (and a shipping expense) to get them swapped out. I'd rather fix them here if possible, but that's seems to be a longshot since no one seems to know what's causing it.

 

[gaijin4ever]

I just decided to do some testing with freeze spray (air can turned upside down) to see if I could isolate what part was causing the suspected overheating (by manually spot cooling with the spray, and learned something new and perhaps revelatory. On the 3200C with the problem the longest I just tested, if you remove the lens cover, the blinking stops. As SOON as the lens cover drops into the FIRST thread (even before turning), it starts again. I'm wondering now if it isn't a grounding problem by improper assembly at the factory...

This may be fixable in the field.

 

[ex123yz]

I experienced the same with the lens cover. So maybe ir reflection off of the lens back at the sensor?

 

[networkcameracritic]

I just noticed my hfw3200c started doing it too.

 

[gaijin4ever]

I experienced the same with the lens cover. So maybe ir reflection off of the lens back at the sensor?

I don't think it's a reflection, because if you lift the camera guts out an inch or so, then rest the lens cover on it without the threads touching the body, it doesn't do it. But if it's IN the body, and the metal threads touch the metal body, it DOES do it. I was able to insulate the 4 points where the ring touches the body with electrical tape and I got it back in and the cap on with no blinking. It went all last night without blinking. We'll see if it holds.

This will be irritating to fix if that's the process I have to do to get them to stop blinking, but at least I don't have to send them back to China.

 

[gaijin4ever]

I just noticed my hfw3200c started doing it too.

How's your relationship with your Chinese suppliers? Do you think you can get a definitive answer about what's going wrong?

 

[gaijin4ever]

Doing the fix with electrical tape to isolate the center ring has solved the flashing night vision on all my cameras. The only down side is the two Philips retaining screws inside and two hex screws outside cannot be used because the tape expands the camera part on the rail a little too much and the outer holes don't line up. I just put them in a small baggie for safekeeping until I have time for a more finished solution that will allow them to be used again.

The lens cover, however, does more than enough to hold the guts in place, and they don't move much even when you remove the lens cover. Completely worth the tradeoff of not having to spend $100+ to send them back to the vendor in China for replacement.

 

[ex123yz]

Interesting, I got to try it on mine when I get some time to climb up there.
Can you post some pic on where you added the tape?

 

[gaijin4ever]

I'll try to take some pics today.

 

[networkcameracritic]

Sent of the question to one of the distributors to see what they have done. Can contact China, but tonight.

 

[gaijin4ever]

Sent of the question to one of the distributors to see what they have done. Can contact China, but tonight.

At least I've found a workaround that solves the problem so my camera stop driving me insane at night. Should help others with the problem that don't want to send theirs back, either (or are out of warranty).

 

[gaijin4ever]

Okay, here's the pictures. In the first one, the sunshade is already off, and it's pointing out the two hex screws that will have to be taken out (Once they were unscrewed for this pic, I pried them out with a tiny jeweler's screwdriver - they have a plastic ring also that holds them in, and you can't put the sunshade on with them up). The second picture shows the Philips screw that needs to be removed to slide the camera assembly out (there's one on each side). The third picture shows the black electrical tape installed under and over (one piece wrapped around) the screw shelf and the steadying shelf on the bottom. The last picture shows the black electrical tape installed on the other two protrusions. When that's done, slide all that back in and put the cap on carefully (don't force it and cross thread!) and your night vision blinking is solved.

This was on 3200CN Dahuas. If anyone has another model doing the same thing, it will be interesting to note if this fix applies to other Dahua models with the issue, too.

 

[networkcameracritic]

Seeing this I'm confused than before. So I understand this, what are you isolating the center ring from with the electrical tape? Are you isolating it to prevent a short?

 

[ex123yz]

Thanks for the pictures. Very helpful.
I will need to find some time to do this.

 

[gaijin4ever]

Seeing this I'm confused than before. So I understand this, what are you isolating the center ring from with the electrical tape? Are you isolating it to prevent a short?

I'm isolating the center from the metal casing by covering the metal wings in the assembly with electrical tape. Without this, when the metal lens cover touches the metal casing, the blinking starts.

 

[networkcameracritic]

Ah, so you think it's maybe a ground issue, that would make sense.