Running a CCTV camera off of a 12V battery - Not working!?

[arabidopsis 0]

I am building a remote CCTV camera system that will record to a portable DVR. The ultimate purpose is that I am going to send it 100 meters underwater in an aluminum case to watch fish behaviour. But that isn't important right now.

 

What is important is that my camera isn't running off the battery for some reason. The camera is the Clover Electronics OB280... just a basic IR camera with a decent picture.

 

It's power requirements are 12 VDC, 250 mA at peak usage. I have a 12 volt Sealed Lead Acid battery. This CCTV camera comes with an AC wall adapter, and everything works just fine when I use that. It uses a barrel plug connector.

 

So I bought an identical connector, soldered the appropriate wires to my SLA battery, and figured everything should be fine. However, it doesn't work when I plug the camera to the battery.

 

I checked the voltage with my multimeter, from the battery it's 12.5 V, from the AC adapter it comes out at 11.9 V, so it should be within the correct range. My polarity is not backwards, as in both cases the center of the plug is positive and the outside is negative.

 

Does anyone have any ideas as to what could be wrong here (or how to go about finding out?)

[shoreviewsecurity 0]

Hi and welcome to the forum...

 

The only thing I can figure is that the battery will show 12VDC but under a load drops below the camera threshold. When the cam is connected to the battery, what is the voltage reading.

 

Is it an older battery?? I have done this in the past but have connected several batteries together in order to get the components to work under load.

 

Hope this helps

 

Mike

[arabidopsis 0]

Hi and welcome to the forum...

 

The only thing I can figure is that the battery will show 12VDC but under a load drops below the camera threshold. When the cam is connected to the battery, what is the voltage reading.

 

Is it an older battery?? I have done this in the past but have connected several batteries together in order to get the components to work under load.

 

Hope this helps

 

Mike

 

The battery is fairly new and is freshly charged. I have a second one that I'll try tomorrow to see if it's a battery issue. Hopefully the stupid thing isn't broken.

[zmxtech 0]

100m of cable might have to much voltage drop for sure. what you can do is

use two 12v batteries in series to make 24v and use a regulator to send out 12v+the drop might be 15v or so.

 

easy to make with a LM317 etc http://www.aaroncake.net/circuits/supply.asp

for example

 

z

[Squiffy 0]

I assume you're testing it locally rather than running it through 100m of cable at the moment.

 

I would double check the barrel connector - are you absolutely certain it's identical? Some of those have fractional differences in dimensions that are hard to see with the naked eye. I try to harmonise my connectors on all my 12V equipment to 2.1mm to avoid these problems.

[Soundy 1]

100m of cable might have to much voltage drop for sure. what you can do is

use two 12v batteries in series to make 24v and use a regulator to send out 12v+the drop might be 15v or so.

 

easy to make with a LM317 etc http://www.aaroncake.net/circuits/supply.asp

for example

 

z

 

Just a thought on this: if voltage drop proves to be the issue, you can try this method, but should consider putting the regulator in the case WITH the camera... then the voltage can drop up to a full 10V or so over that 100m run, but the camera will still get a solid 12V.

 

Remember too, with an IR camera, you'll see substantially more draw once the IR LEDs turn on, and over a 100m run, that will cause even more voltage drop. Again, a higher supply voltage and a regulator right by the camera will counter this.