Power Supply Voltage drop when connecting load

[fanwasy]

I have power supply 12V, 10A , its works and i got 12V DC , but when i connect a device
cctv Camera the voltage drops to 5 volts and the Green led stars to blinking.

 

[d123]

Hi,

Can you explain what the blinking LED signifies, please? Is there a user manual for that power supply? What are the camera operating ratings, and I guess someone else might ask you how they are connected and if you could provide a schematic of your circuit.

 

[dick_freebird]

Is the camera supposed to work from 12V, or 5V? Could
be that there is some input overvoltage protection on a
5V supply camera that is clamping the voltage and hitting
the current limit.

Abruptly connecting a load with a large decoupling bank
inside it, could trigger a latched overcurrent protection
(where attaching camera first, then turning on supply,
might be OK under the supplie's soft-start control).

 

[fanwasy]

Thank you for your replay. The Power supply was worked perfectly it's provide 4 CCTV cameras a power of 12V , 5watts each camera consume. But after 6 moths the cameras stop working , I have checked the cameras power plugs the reading of voltage is 5 Volts, when I unplug the 4 cameras and check the voltage the reading is 12 volt.

- - - Updated - - -

Is the camera supposed to work from 12V, or 5V? Could
be that there is some input overvoltage protection on a
5V supply camera that is clamping the voltage and hitting
the current limit.

Abruptly connecting a load with a large decoupling bank
inside it, could trigger a latched overcurrent protection
(where attaching camera first, then turning on supply,
might be OK under the supplie's soft-start control).

camera rated 12v 5W

 

[d123]

Hi,

Have you tried disconnecting one camera at a time to see when the voltage returns to a normal 12V?

I don't know, it sounds to me like there may be a shortcircuit/faulty part or wiring somewhere dragging the voltage down. It does sound like - amongst many possibilities - it may be current-limiting or something along those lines. Perhaps measuring the current going in to each camera (if possible and connecting one at a time) might shed a lot of light on where to start looking properly for the cause of the problem.