ACD 1500 Failure - Need to disassemble

[Rick.D.Parker 0]

Hello,

 

I have an ACD 1500 which failed in the Texas heat. It appeared to be a power issue so I checked the wall wart and I was producing 24VAC. I then tried replacing the wall wart, however, this did not solve the issue. At normal start up, the PTZ runs a returns to home and then returns to the last known position. Now, when I apply power there is no movement and no video.

 

I took the camera back to the store that I bought it from, several years ago. The wall wart was their first thought as well, however, when that did not correct the issue, they told me that it was the AC to DC converter board. They told me that they tried for three weeks to find this board, but was unsuccessful and that there was nothing else that could be done.

 

I tried to disassemble the ACD 1500, however, I have not been very successful. I tried Google for an answer, however, I was unsuccessful there as well. Has anyone been able to disassemble one of these cameras or can anyone point me to a document that could assist me? Any help is appreciated. Thanks.

[Birdman Adam 0]

Yea, I'd say the power circuit/board is dead.

 

If you know how to build basic circuits and understand electricity, you could probably make your own replacement.

 

First you need to know what voltages and current the camera needs (internally, at DC consumption, not the main power needs). This would probably involve a 2:1 transformer to take 24VAC to ~12VAC, a diode bridge to make chopped DC from that AC, some capacitors to smooth that out before a linear regulator. The camera probably needs basic standard voltages, like maybe 12v for motors, maybe 3.3v for circuitry, or commonly 5v. Linear regulators can take the smoothed DC to nice voltages like 5v (number LM7805), or 12v (LM7812). With another small cap on the output (say 10-100uF), you are good to go!

[Rick.D.Parker 0]

Thanks Birdman. I can build a small converter, the volts/amps is where I am at a loss. I can assume the camera is 12VDC, but I have no idea about the fan/heater and ptz.

 

I thought a good first step would be to tear down the camera. That's where I am stuck. I can't find any data on how to break it down. Any suggestions or website you think may be useful?

[ak357 0]

Yea, I'd say the power circuit/board is dead.

 

If you know how to build basic circuits and understand electricity, you could probably make your own replacement.

 

First you need to know what voltages and current the camera needs (internally, at DC consumption, not the main power needs). This would probably involve a 2:1 transformer to take 24VAC to ~12VAC, a diode bridge to make chopped DC from that AC, some capacitors to smooth that out before a linear regulator. The camera probably needs basic standard voltages, like maybe 12v for motors, maybe 3.3v for circuitry, or commonly 5v. Linear regulators can take the smoothed DC to nice voltages like 5v (number LM7805), or 12v (LM7812). With another small cap on the output (say 10-100uF), you are good to go!

 

And one more cap about 100 nf across output would be nice

[Horizon 0]

G'day Rick. My suggestion is that once you've managed to pull the camera apart, take a look for faulty capacitors. They'll look something like these

http://en.wikipedia.org/wiki/Capacitor_plague

they may have dried out and failed when the camera overheated. If the top of the cap has become domed, then it needs to be replaced. See if you can find where the power supply is. The capacitors around the supply are under the most stress, and tend to fail first.

Good luck!

[Rick.D.Parker 0]

Ok, I'll try to figure out how to disassemble the camera and if I can figure that out, it should be easy to find the power board and identify any damaged caps. I have been unable to find any information on the dis-assembly process, but I'll try to figure it out without damaging anything else.

 

Thanks for everyone's help.