capacitor depress voltage problem please help.

Discussion in 'The Projects Forum' started by iamhere, Oct 5, 2009.

Thread Status:
Not open for further replies.
  1. iamhere

    Thread Starter Active Member

    May 1, 2009
    33
    0
    Hello all ,

    I am intend to use capacitor to get 5ma 5V DC from AC220V power. I know there are many circuits on webisite can be found, but here the difficulty is, I want to connect the GND of 5V DC to GND of main DC(about 340V) so my mcu can control the other high voltage DC circuits,please check my circuit. the problem is, I test the voltage of CV2 and CV3 are very low,seems not charged. could you please give me some tips to make the circuit working ?


    Thanks a lot for your help. waiting.........

    Best regards,
     
    • v5.jpg
      v5.jpg
      File size:
      19.2 KB
      Views:
      48
    Last edited: Oct 5, 2009
  2. iamhere

    Thread Starter Active Member

    May 1, 2009
    33
    0
  3. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
    Attempting to rectify and use the line voltage directly is only creating a deadly shock hazard. Without transformer isolation, every part of the circuit must be assumed to carry a lethal voltage. The value of you capacitors will only give a desired output for one small range of load resistance, as well.

    Using such a circuit will be very dangerous. Anybody coming in contact with any part of it may receive a lethal shock.

    You need to use a step down transformer to produce an AC level that can be rectified and regulated to make the 5 volts DC. It is simply too dangerous to try to use your circuit.
     
    Last edited: Oct 5, 2009
  4. iamhere

    Thread Starter Active Member

    May 1, 2009
    33
    0
    dangerous problem can be ignored, this is part of circuit for a high voltage device design. people will never have chance to touch it. just like your 110v or 220v power cable, swith and lamps in your room, although they are dangerous too, but you will not consider to use a transformer to change the voltage below 30v first ,right?
     
    Last edited: Oct 5, 2009
  5. iamhere

    Thread Starter Active Member

    May 1, 2009
    33
    0
    Just please help me to get the 5ma 5V DC,thanks.
     
    Last edited: Oct 5, 2009
  6. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
    It is not a safe circuit to play with, and so violates some of our rules -


    Forum members must not knowingly provide any information that may adversely affect another member; this includes, but is not restricted to, information that may potentially result in injury, death, damage or destruction of property and possessions. The administration takes this matter seriously and has the right to remove any contentious content and deal with the offending member as it deems is necessary.

    Always use a transformer to reduce line voltage and provide safe isolation.
     
Loading...
Thread Status:
Not open for further replies.