hi team : sorry for my poor English writing ( i am Arabic) it its the first time i post here ...so i searched many times on google but i did not found my problem. i built my cnc machine finally , so every things adjusted and work fine and smooth . my problem : when i turn on the spindle all axis moving without stop , when i turn off the spindle every thing work good ------------------------------------------------------------------------------- the inverter is LS taype my spindle is 4 wires ( u-v-w-gnd) the gnd not connected . stepper motor type sanyo 24 volt my driver is tb6560 new version (NOT old one that need some modification to work probably ) the gnd of the pc is not connect directly to the power supply gnd of the driver....as i think it is isolated . i connect the body of my cnc and the stepper motors body to the dc gnd . but i still have same problem.