3hp motor contactor size 22A or 40A?
To avoid oversizing in this case, would i need to provide additional fusing to help protect the 3HP motor if it has a 40A contactor as opposed to a 22A?


No. Fuses are not for protecting the motor they are for protecting the wiring and other current-carrying components from short circuits and ground faults. They also prevent a fire if the motor or motor protection fails. An overload relay, motor protective circuit-breaker or temperature detecting device in the motor are the possible motor protective devices. The motor protective devices are always selected and adjusted based on the motor ratings, Hp &amp; voltage, current or winding temperature.


  There is also a 40A overload to be used with this 40A contactor. It jus means the overload and contactor can handle up to 40A each


It does not just mean it can handle 40 amps. The 40A overload may not be appropriate. Some have interchangeable current sensing parts that allow a wide range of motors, and some are adjustable. However there is a limit to the range of motors for which they are appropriate. The documentation for the overload tells what motor voltage &amp; power or current for which they can provide appropriate protection.