10.) The non-use of a locking type disconnect for submersible well pump motors.
Section 430.102(A) requires the installation of a disconnecting means in sight from the motor controller location that disconnects the controller. In the case of the typical residential submersible well pump installation the controller would be the pressure switch on the water storage tank. Section 430.102(B) requires a disconnecting means in sight from the motor location to disconnect the motor. Article 100 defines "in sight from" to be visible and within 50'. So there should be a disconnecting means that is visible and located no more than 50' from the well head unless the installation qualifies to meet exception No. 1 to 430.102(B) which allows you to eliminate the motor disconnect if the controller disconnect is capable of being locked in the open position.
Example: a submersible well pump has been installed to supply the domestic water for a dwelling unit. The pump cable runs from the well head to the dwelling unit basement where it connects to the load side terminals of the pressure switch located on the water storage tank. A branch-circuit has been run about 35' from a panelboard, that is not visible from the water storage tank location, to a snap switch located next to the water storage tank. The conductors on the load side of the snap switch run to the line side terminals of the pressure switch. In this case the snap switch would be the controller disconnect switch required by 430.102(A). If the panelboard were visible for the entire 35' from the water storage tank location the circuit breaker could also serve as the controller disconnect.
In the installation described, it is impracticable to mount the disconnecting means within sight from the pump motor so the exception to 430.102(B) is applicable. Note that provision for locking or adding a lock to the disconnecting means must be permanently installed on or at the switch. There are products available on the market that will allow a lock to be placed on a standard snap switch assembly or circuit breaker.