According to the datasheet the winding resistance is 6.5R and the current 1.75A, so they are actually 11V motors driven from a 325V supply.
I don't think I have seen a stepper motor with a DC rating more than 24V. There isn't much point in putting lots of thin wire in the coils as it makes the inductance high. Better to fill the same space with less turns of thicker wire. The only down side is more I2R losses in the drive circuit.
I don't think I have seen a stepper motor with a DC rating more than 24V. There isn't much point in putting lots of thin wire in the coils as it makes the inductance high. Better to fill the same space with less turns of thicker wire. The only down side is more I2R losses in the drive circuit.