Quote Originally Posted by m_c View Post
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Now as I mentioned earlier about theory and real world, using a reasonably accurate multimeter, I get around 52VDC at the capacitor. That's a good 14% higher than our calculated figure. This will drop under load, but it may also rise above that under hard deceleration of motors, which is why you should always allow a reasonable safety margin between your power supply voltage and the maximum allowable stepper driver voltage.
Your driver EM806 has operating voltage up to +80 VDC so why 52VDC satisfy you?