Four-way monitoring switching power supply is not just a camera circuit can all the way? Or is there a problem with the equipment or line? The camera will appear short-term flash, shaking, black screen phenomenon.
Now is the four cameras are connected to the positive and negative, the power is 12V6.3A, plus a small 12V1A power alone access to a camera, the results of a separate shine, the last black screen. The original problem of the camera or a problem, no problem or no problem. And the fault is short, I suspect that the camera problem, but the manufacturers that no problem. Depressed ah! Which a master to help one.
There may be insufficient power supply, you add a block power.
Power supply is insufficient, four of the best choice of five or more switching power supply!
The best is to buy a single 12V1A power supply and then 220V directly to the camera in front, then take 12V1A power supply, so no power attenuation
I understand that this is the case where you have four monitor cameras and are on a power cord, so that the line pressure drop is too large, resulting in loading the voltage on each camera is too low.
Because your problem is not very clear, such as wire diameter and length, the camera's rated current, etc., here I make a hypothesis: the camera's rated voltage of 12V current of 1A (general working current of 0.4A or so), diameter For 0.5 square mm, the power cord to the camera length of 50 meters, switching power supply for the DC12V5A.
1) Single camera resistance: R = 12 / 0.4 = 30 ohms
2) 4 cameras and the total resistance on a line is: R total = 30/4 = 7.5 ohms
3) Resistance on line: R line = Resistivity * L / S = 0.0175 * 50 * 2 / 0.5 = 3.5 ohms (actually greater than this number)
4) The voltage assigned to the camera U = IR = 12 / (7.5 + 3.5) * 7.5 = 8.2V
Solution: switching power supply in the power of about 60W is (DC12V5A) on it, the amperage is not the bigger the better, as long as the camera is not less than the total rated current can be, the power cord to a camera Line to reduce the total current to reduce the voltage drop on the power line, the diameter of the distance to see your distance, generally within 100 meters with 1 square mm line.
