1.1.5 How are rotors with a feather key balanced on the IP23 electric motors?

The rotors of all standard electric motors as well as IP23 motors are dynamically balanced with an inserted half key according to DIN ISO 8821. Drive elements such as pulleys, couplings, and pump wheels must also be dynamically balanced with an inserted half key. Care must be taken that the hub length and the length of the keyway match so that no additional residual unbalance occurs. Upon request, full key balancing is also possible.