On Fri, 21 Jun 2024 at 12:14, Viesturs Lācis <viesturs.la...@gmail.com> wrote:
> The question I am trying to solve at the moment is DC supply for 8i20 Both my lathe and mill use 8i20s on the main axes. In both cases I use a single power supply shared by all the drives on the machine. The supplies are a simple rectifier and capacitor except that I also have resistors and relays for soft-start and capacitor discharge. Discharge is handled by a normally-closed relay that opens when the PSU power is turned on. Soft start on the lathe is handled by a HAL component, as the 8i20 returns bus voltage on smart-serial If the 8i20 bus voltage is above a few volts I do not allow the PSU to turn on. (to protect the relay contacts from welding) Then, when the PSU turns on it is powered through a power resistor to limit the surge. Then when the HAL component sees something close to full bus voltage it switches an output that closes a relay that bypasses the soft-start resistor. The mill PSU has a 555 timer for soft start, and I like this less than the HAL component as a solution, My system does not have any isolation between the DC power and mains, it is just a simple rectifier/cap. If you add a 3-phase transformer you will have much less input ripple and will also have some isolation. If I could find a suitable transformer cheaply I would use one. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
