I have the parts to build a variable dual-rail DC power supply. These include:
800VA, dual 60V secondary transformer
100V caps, in sufficient amounts of capacitance
50A monolithic rectifiers
10A variac, 0-100% mains voltage range
fusing
digital DC voltmeter module
My general wiring plan is to connect the variac to the mains, the variac AC output to the transformer primary, then the secondary to the rectifier, and finally a CRC type cap bank (I can use up to 100,000uF total capacitance split between the two rails and CRC) with rail voltage monitoring via the digital meter.
My primary goal with this is to have something to power most any kind of amp board or chip amp that I might want to test and to have the capability to vary the voltage of the rails as needed/desired. With an 800VA transformer and lots of capacitance I should have a nice stiff power supply with low ripple.
So, my question is:
With the variac first in line, can I just dial the voltage ratio down to zero before turning on the mains power and then dial it up to whatever I need? Will this mean I don't need to worry about a soft start as long as I don't forget to start at zero each time?
Also, what's the best place in the circuit for the fusing?
Any other comments on this setup are welcome. It will be primarily testing of DIY amp kits that I build or buy.
Thanks,
-Charlie
800VA, dual 60V secondary transformer
100V caps, in sufficient amounts of capacitance
50A monolithic rectifiers
10A variac, 0-100% mains voltage range
fusing
digital DC voltmeter module
My general wiring plan is to connect the variac to the mains, the variac AC output to the transformer primary, then the secondary to the rectifier, and finally a CRC type cap bank (I can use up to 100,000uF total capacitance split between the two rails and CRC) with rail voltage monitoring via the digital meter.
My primary goal with this is to have something to power most any kind of amp board or chip amp that I might want to test and to have the capability to vary the voltage of the rails as needed/desired. With an 800VA transformer and lots of capacitance I should have a nice stiff power supply with low ripple.
So, my question is:
With the variac first in line, can I just dial the voltage ratio down to zero before turning on the mains power and then dial it up to whatever I need? Will this mean I don't need to worry about a soft start as long as I don't forget to start at zero each time?
Also, what's the best place in the circuit for the fusing?
Any other comments on this setup are welcome. It will be primarily testing of DIY amp kits that I build or buy.
Thanks,
-Charlie