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???
08/02/07 09:53
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Msg Score: +1
 +1 Good Answer/Helpful
#142634 - Droop
Responding to: ???'s previous message
A rectifier-capacitor network only charges the capacitor during the peak part of the AC cycle. After that point, the load current discharges the capacitor until the next AC cycle peak. If you are measuring 270V DC on load, then that is the average voltage on the capacitors and there will be a 60V peak-to-peak ripple on top of the DC voltage.

If or when you plug the circuit in, the inrush current will be significant, and in my experience it will be at least ten times the load current (10A load - 100A inrush?). It will also depend strongly on the phase angle when the circuit is connected, so your components may survive 99 starts and then fail on the 100th.

In most countries the circuit you describe will not be permitted because the current drawn from the AC supply is not sinusoidal. You will need to look at the relevant regulations, and I suspect you will need a PFC (power factor corrected) front end rectifier. A PFC circuit will usually limit inrush current to reasonable levels.

List of 9 messages in thread
TopicAuthorDate
Bridge Rectifier voltage drop            01/01/70 00:00      
   Droop            01/01/70 00:00      
      the danger of using a voltmeter            01/01/70 00:00      
   Hidden voltage drops            01/01/70 00:00      
      Its a three phase bridge rectifier            01/01/70 00:00      
         Filtering or regulation            01/01/70 00:00      
            also            01/01/70 00:00      
               Unfortunately...            01/01/70 00:00      
                  bridge can handle upto 60A            01/01/70 00:00      

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