can't find solution

[surv_manager 0]

Hello,

I have 2 Kalatel CyberDome series PTZ cameras. I am having issues with one of them. I have intermittent video loss, in 5 to 6 second spans while in tour mode. If I have the PTZ sitting still, it will record all day everyday, but in tour mode I lose video for 5-6 seconds at a time at a rate of once or twice an hour. When I lose the video feed, the tour remains in motion. Therefore I assume it is not a power issue. Everything between the 2 ptz's is identical; length of cable, setup, everything. 24VAC power, coaxial cables with BNC connectors at the dome and the dvr, RS422 line running from the back of the Digiplex IV matrix spliced in with a KTD-405 controller pad, and an RJ45 connector jack from the camera to the power/video lines. As mentioned I have control of the camera with the joystick, and it maintains in motion during video loss. I just do not know where to begin with finding what the problem is. Any suggestions? BTW, the video loss is never at the same point in the tour, and the loss is not in equal times between them. Thank You.

[Soundy 1]

Could still be a power issue, if the voltage is dropping just enough for the camera module itself to shut off but nothing else. What size wire are you running, and what's the distance? What are the power (watt) or current ratings for the cameras?

[surv_manager 0]

I have 22 Gauge wire running 169 feet total. They require 16 VA minimum. I have 22 VA at the module. Allowable voltage range is 20 to 28 Volts. I do not know the watt ratings, just the volt ratings.

[Soundy 1]

16VA *minimum*, but what is the maximum? The more current the camera draws, the more voltage will drop... with the PT motors running, it's going to be drawing a lot more current than at a standstill. With 24VAC input, 16VA will be 0.67A, but if that's a MINIMUM, what's the MAXIMUM it will need?

 

With 24VAC input, assuming 1A (24VA), you're going to see about 5.5V drop over 22 AWG, meaning you only get 18.5V at the camera.

 

Ultimately, that wire is way too small to be powering a PTZ. You want to use AT LEAST 18 AWG, preferably 16.

[surv_manager 0]

The maximum it will need is 24 VA, with a minimum of 16 VA. I apologize for the confusion here.... running to the PTZ's is 18 Gauge wire at 169 feet wire length. 22 Gauge wire is what powers the stationary cameras throughout the rest of the building. I apologize for informing incorrectly.

[Soundy 1]

Okay, well, 24V @ 24VA is 1A, over 18 AWG at 170' gives you a bit over 2V drop at maximum draw. It SHOULD be okay... but it's borderline. The behavior does sound like a power-drop issue, like it's just skirting the lowest voltage it will work with, and at times it's dropping just enough for the camera module to drop out. If you have a 20-24VA power supply, that could be the issue too, as its output will drop once you pass its capacity... and as the transformer's output voltage drops, your loss over the wire will increase exponentially.

 

It sounds like a combination of factors, powering the thing with the bare minimum requirements, and when it hits that ceiling, you get that "perfect storm".

 

At the very least, try increasing the transformer to a 40VA model, perhaps even one that does 28VAC output... see if that doesn't cure your problem.

[surv_manager 0]

thank you so much for your suggestion. I probably never would have fixed it, because i was assuming it could not have been a power issue. But thank you, I will try it out and if it doesn't work I'll post come back. But thank you for your time.

-Tyler

[surv_manager 0]

So as I mentioned earlier, I have two PTZ's and only one of them is having this problem. Here is what I did. I rewired them both, by swapping the wiring. I used the power and video feed from the good PTZ and wired it into the problematic PTZ and used the wiring from the problem PTZ on the good one. I expected the problem to swap between PTZ's but it didn't. I still have the same problems on the PTZ. Does that make the source of the problem internal to the PTZ?

[Soundy 1]

Possible... but have you eliminated a power issue by upgrading the one camera's power supply? If the troublesome position's power run is longer or for some reason shows slightly higher resistance, the problem would remain with that position - again, it really sounds like a "perfect storm" of borderline power components.

[Blake CCTV 3]

Could it be an intermittent connection on the cameras slip ring connection does it happen in a particular spot and does it happen when you pan it and tilt it or just pan or tilt