Additionally, the rated voltage of a motor (UN) does not need to match the maximum supplied voltage (Umax). It is acceptable to supply higher or lower maximum voltage to the motor as long as it falls within the maximum continuous operating range. For example, a motor with a rated voltage of 48 V (UN) can be used with a power supply that has a maximum of 24 V (Umax). A new speed-torque curve would need to be calculated with the reduced voltage; however, it might better match the operating point. This is a very useful hint during motor selection. Figure 11 demonstrates the effect of a lower applied voltage (Umax= 24 V) compared to the motor’s rated voltage (UN = 36 V); the yellow operating point lies closer to the operation range boundaries when the maximum supplied voltage is 24 V.
