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Kai Klaas
01/20/06 06:10
  01/20/06 06:14

Read: 767 times

#107874 - Storage cap
Responding to: U Kaz's previous message
U said:
Everytime machine will perform an operation current will go high as much as 13-15Amps for a second. and at some of the busy places the machine is doing at least 150- 200 operations a day in 8hour working time.

With full wave rectification storage capacitor must provide all the current for a worst case duration of about 10msec. According to C = Q / U = I x t / U for a maximum voltage drop of 3V about 50000F would be needed for the storage cap. This is no problem for a good toroid transformer.

But needed current rating of transformer also depends on stiffnes of transfomer, not only on motor current being drawn from it. By other words, the transformer must be able to charge up the storage cap every 10msec additionally to delivering the motor current of 15A! For this it must be stiff enough. This is the reason why the current rating of transformer must be some higher than 15A. With a too weak transfomer the voltage drop at storage cap will be much much higher than the estimated value above.

In any case you will need a soft start for the transfomer.


List of 40 messages in thread
Power supply      U Kaz      01/18/06 04:37      
   Book Horowitz and Hill      Oliver Sedlacek      01/18/06 06:36      
   all and every PS chip manufacturer has a      Erik Malund      01/18/06 06:53      
   Not enough information      Steve M. Taylor      01/18/06 06:54      
      more information here      U Kaz      01/18/06 08:56      
         Unregulated then      Steve M. Taylor      01/18/06 09:33      
            will these components do?      U Kaz      01/19/06 02:30      
               Overspecced      Steve M. Taylor      01/19/06 02:57      
                  Surge current, cooling      Kai Klaas      01/19/06 06:24      
                     Words of wisdom.      Steve M. Taylor      01/19/06 08:05      
                        count me in      Erik Malund      01/19/06 08:35      
                        Exactly      Kai Klaas      01/20/06 06:13      
                           ALWAYS.      Steve M. Taylor      01/20/06 06:43      
         How about . . .      Hal Albach      01/18/06 13:08      
            Energy Storage Capacitors        Andy Neil      01/19/06 04:23      
               transformer      U Kaz      01/19/06 04:50      
                  NO.      Steve M. Taylor      01/19/06 05:34      
                     20A?      Andy Neil      01/19/06 06:13      
                        some transient      Erik Malund      01/19/06 07:00      
                           And,...      Steve M. Taylor      01/19/06 07:59      
                              re: And...      U Kaz      01/19/06 08:40      
                                 Now you're talking      Steve M. Taylor      01/19/06 09:19      
                                    Are you sure?      Andy Neil      01/19/06 09:37      
                                 Storage cap      Kai Klaas      01/20/06 06:10      
                                    an element of fuzzyness      Erik Malund      01/20/06 06:49      
                                       My problem too      Steve M. Taylor      01/20/06 08:34      
                                          Fuzzy...      Andy Neil      01/20/06 09:28      
               ???      Steve M. Taylor      01/19/06 13:41      
                  !!!      Andy Neil      01/20/06 09:27      
   Is this okay...?      U Kaz      01/23/06 06:53      
      Have you read my last post?      Kai Klaas      01/23/06 07:27      
         I did.      U Kaz      01/23/06 08:06      
            Reliable or not ?        Farshid Jafari Harandi      01/23/06 08:27      
            Farnell      Steve M. Taylor      01/23/06 11:40      
               re: Farnell      U Kaz      01/23/06 12:24      
                  so farnell do not know how to copy      Erik Malund      01/23/06 12:40      
                  Whut ?      Steve M. Taylor      01/23/06 13:13      
                     sorry, but what is this ??      U Kaz      01/23/06 14:58      
                        typo      Steve M. Taylor      01/23/06 15:09      
      Ok in winter, problematioc in summer      Erik Malund      01/23/06 07:40      

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