How do you determine polarity on cameras?

[boybloo 0]

I have a camera that had the connectors cut off. I want to solder connections back on and I was able to determine which line was video and which is power but I can't tell the polarity of each.

 

Does it matter, and if so how can I determine polarity. Is there color indicators?

[rory 0]

If its 24VAC camera then it doesn't matter. If it is 12VDC it will matter, unless it is a very expensive camera it would not have reverse polarity built in and then it would get fired.

 

If the power wire has a braided outer, that is ground, while the center would be positive - typically. Best to look for a manual for it though, or some specs, unless you are willing to wing it and hope for the best. If you can get a photo post that also.

[boybloo 0]

Wow! Over 12,000 post & from Nassau - What's up 242?

 

The camera is 12v dome. It has a single wire running to a rubber block and four wires running from there. I do know power vs video. The wires in both are red & white. Some of the insulation above the block has been removed & I can see a white wire, a red wire and some uncovered strands.

 

I've checked the continuity and when I check the uncovered wire against all of the end wires there is continuity. When I disconnected the cable from the camera and checked I have continuity on the 2 red wires but not the 2 white.

 

This I think means that the white wires are positive but (dumb question). What was the difference?

[rory 0]

Hey whats up

 

Hard to tell without seeing it, do you know the model of the camera?

If you can get a photo of it that would help also. If you cant upload it then you could email it to me.

 

Basically if you put the incorrect polarity into it, it will fry the power section, and then it wont work anymore

 

Red is normally positive, black would typically be negative. If it were between red and white though, I would think white would be negative. But then it depends, some brands mix that right up also.

 

All nighter here, so im off to sleep for an hour. Will check back in later.

Rory

[survtech 0]

Check continuity to the camera body. Anything that measures a short should be ground.

[boybloo 0]

Thanks survtech, I got it - continuity saved the day.