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can any one tell me if I use capacitive reactance to drop voltage from 220v ac to 12v and then use bridge rectifier to get polarity, now output from the bridge rectifier can shock me with respect to the earthing. in simple word can get a shock from the output.

Siddhartha Sadhukhan
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  • I think so... can you post a schematic of what you have in mind. (Is there some resistive load after the capacitor?) – George Herold Jun 28 '16 at 16:38
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    There is no reliable way to make a capacitor power supply that is touch safe. – KalleMP Jun 28 '16 at 19:00
  • Please use proper punctuation, if you want a professional answer, then ask a professional question. Please also see http://electronics.stackexchange.com/help/how-to-ask for guidelines on asking questions. There is no question in your post, please ask a specific question and provide the necessary information to help us answer your question. – Voltage Spike Jun 28 '16 at 22:10

1 Answers1

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Can you get a shock by directly touching the 220V AC live wire?

YES.

Does a bridge rectifier somehow stop you getting a shock?

NO.

Would an isolation device such as a transformer stop me getting a shock?

YES, more than likely but you can still detect a small tingle on some transformers.

Is a bridge rectifier an isolation device?

NO.

Andy aka
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  • yea I got this. with respect to earthing the potential difference become nearly 210 v. – Siddhartha Sadhukhan Jun 28 '16 at 17:34
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    Would upvote this ten times if I could. A capacitive dropper for a power supply is dangerous and can only be acceptable if the circuit is fully isolated from users. – marcelm Jun 28 '16 at 18:34
  • so in the case of mobile charger how does it works. I mean they don't have bulky transformer which is capable of supplying 1amp or 2amp current. – Siddhartha Sadhukhan Jun 28 '16 at 19:16
  • Please link to one of these chargers so an explanation can be given but more than likely it does have a high speed switching transforer that can pass power at a tiny fraction of the size of a regular AC power transformer. – Andy aka Jun 28 '16 at 20:35
  • that means, by using clock they pass the voltage for some time and don't allow to pass the voltage for some time like SMPS to a small transformer which literally isolate the main line from output line without exhibit the heat. – Siddhartha Sadhukhan Jun 29 '16 at 08:15
  • I don't understand what you are saying and any power transformer will get warm. – Andy aka Jun 29 '16 at 10:27