Response to R SEDLAK's Message of 12/24 
 
In the ideal sense one would only "RIP OFF" electrons from the anode 
thereby solubilizing copper to be used/plated at the cathode.  That's a 
simplistic definition of an electrochemical cell (i.e, operating with DC 
current).  I would add that the current and the voltage give rise to 
plating POWER. 
 
In order to achieve this POWER, AC current is converted by capacitor, 
diode, SRC, filter to provide DC power to the plating tank.  AC current 
differs from DC in that a polarity shift occurs with given frequency 
with AC but not DC.  THIS IS THE RUDAMENTARY DEFINITION OF A RECTIFIER 
(A device converting AC to DC power).  BOTH AC AND DC SOURCES COULD BE
CONSIDERED "ELECTRON PUMPS." 
 
R SEDLAK has described ideal palting conditions of the electrochemical 
cell.  The SOURCE of electrons as described has to be DC which is 
generated by a RECTIFIER. 
 
Herein lies the problem with RECTIFIERS.  The power source is never 
purely DC, and in time hardware deteriorates (filters, SRCs, capacitors, 
diodes) generating more and more AC current passage until the plating 
tank only sees AC.  This means that over a period of time the anode is 
the cathode, the cathode is the anode, and SO ON IN A CYCLIC FASHION. 
 
################################ 
 
What I would like to know is what actually is observed with older 
rectifiers? 
 
Probably most shops are not operating at manufacter's AC/DC levels so 
what's the first sign observed of a bad filter, SRC, or diode? 
 
How often do plating shops check their rectifiers; or as seen by some 
responses in the last couple weeks, does anyone really know what the 
AC/DC ratio means to copper plating? 
 
I'm not out to flame the group or R Sedlak for a response which might be 
needed, but it seems these issues are being regurgitated. 
 
IS THERE A COPPER PLATING/RECTIFIER GURU OUT THERE? 
 
THANK YOU.

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