My Steppers running in parallel would need around a minimum of 46 VDC and a max of 57.5 VDC, then converting that to AC it would be minimum 33 V and a max of 41 V with a total of around 245 VA
What the guide is telling me is to use something around a 300VA with a secondary voltage around 38 V
The electronics I have on hand are a Avel Lindberg Y236857 625VA 45V+45V Toroidal Transformer and 400V 25A Bridge Rectifier will these work to build the power supply or do I risk damaging everything? (still need to get the capacitors)
you have a 45V AC transformer which when rectified with some smoothing caps should give a DC voltage of about 65 or a bit more. I assume the toroidals 45+45 means it has two seperate windings which you can use in parralell. Don't use the two in series or you will end up with aboput 130V
As your drivers can handle 80V Dc then should be ok just set the current limit to the same or less than the motor specs.
the other factor to take into account is the transformer regulation
the output small transformers can be 25 % more with little or no load
the output stated on the lable is only correct when fully loaded !
expect the regulation on large transformers like your to be about 6%
so the unloaded output will be 45V x 1.06 = 47.7 RMS
the peak voltage will be root two times 47.7 = 67.45 V , this is what your capacitor will charge up to with no load
fully loaded the capacitor will be charged up to 1.4142 x 45 = 63.64 V less the 1 or 2 volts dropped across the diodes in the bridge rectifier
thats assuming your mains supply is exactly the same as the transformer primary voltage
for a transformer designed for 240V my mains supply of 248V will result in the output being about 3% higher !!!
looking at the Basic Power Supply Design Guide
it may be worth fitting a bleed resistor of about 1 K ohms 10W across the DC output
so you can test the power supply without the G202 drivers being connected
the resistor will discharge the capacitor so your not left with a fully charged capacitor
when you switch off
what size capacitor would work, according to the Cambell worksheet I would need around 36,000uF but I'm only finding those in 40V or 100V which would be best?
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Power Supply Question
