How do we decide to go for single plane, two plane, and multi plane balancing?

In a dynamic balancing requirements the component or the end user decides the number of planes of balancing. In absence of such information refer to the standards. Normally when the length is more than diameter you go for two plane balancing. For disc shaped components like small fly wheels, pump rotors, clutches you can do single plane balancing. In components like multi stage pumps, turbines, crank shafts there will be provision for multi plane balancing. The main reason for multi plane balancing is only for ease of placement of weights.