On label the physical properties are the coil resistance and max current. The voltage is supposed to be a relation of these two in a context where the motor would be supplied with dc voltage. But its not supplied with dc voltage, because the driver outputs a special high freqency (khz) voltage. Driver also senses coil current and limits it at a point set by the user with an adjustable pot on the driver. So it can have higher votlage because the driver will still sense the current and will interrupt the current peak, coils will not get more currrent than allowed, regardless of voltage. In this context users can supply much higher voltages, which helps coils energize faster, helps the motor to run better at higher speed.
So on short, a motor 2,8v label run at 12v psu, that is quite ok, and probably around what most ppls use or should use. Hard to say just from the voltage, but probably motors with 12v label run at 12v psu, these are probably not good.
So on short, a motor 2,8v label run at 12v psu, that is quite ok, and probably around what most ppls use or should use. Hard to say just from the voltage, but probably motors with 12v label run at 12v psu, these are probably not good.