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45 Amp Stud SCR's in place of 45 Amp Stud Diodes

Recently was told I may use STUD SCR's in place of STUD DIODES. I built a small Lead/tin Plating bath and need a RECTIFIER about 5 Volt / 35 Amps to plate the Printed circuit Boards. I have 45 Amp stud SCR's and 70 Amp SCR's. I design and manufacture. I have the chemicals for the plating bath but Rectifier is needed.

Please advise or even let me have diagrams I will construct myself. On the other hand please advise me if I am able to locate diagrams how to construct from the internet.

Christopher Halgryn
- Auckland, New Zealand
2001

An SCR is not a direct replacement for a diode. The SCR must be "switched on" with its third terminal called the gate. Even so the efficiency of diode would be better than the SCR at these voltages. Diodes at these currents are readily available and relatively inexpensive. I like to choose diode current capacity about 1.7 to 2 times its operating current. Remember that diodes in bridge configuration will only conduct for half cycles making the average diode current half that of the output current. In your case 30 to 35 Amp diodes correctly heat sinked will suffice.

Adam Seychell
- Australia
2001