Base assembly for a tower mounted crane

A counterweight tool comprising

• a. an attachment element,
• b. a lever arm,
• c. a weight element,
• d. a first locking mechanism, and
• e. a first crane connection point,
• f. said attachment element being arranged to be attachable to a component of a wind turbine,
• g. characterized in that said lever arm is pivotably connected to the attachment element about a pivot point, said lever arm being pivotable between a first position where the lever arm is arranged at a first angle with respect to the attachment element and a second position where the lever arm is arranged at a second angle with respect to the attachment element, the difference between the first and second angles being greater than 25 degrees,
• h. said weight element being attached to the lever arm at a distance from the pivot point,
• i. said first locking mechanism being arranged to lock the position of the lever arm with respect to the attachment element in the second position,
• j. said first crane connection point being located on either:
• i. the lever arm at a distance from the pivot point or
• ii. on the weight element,
• k. said first crane connection point being arranged such that prior to attaching the attachment element to a component, when a crane lifts the counterweight tool, or just the lever arm and weight element, by the first crane connection point, the lever arm will be arranged at an angle to the vertical of less than 30 degrees and
• l. in that when the attachment element is fixed in position relative to the crane and the attachment element is pivotably connected to the lever arm, then lifting or lowering by the crane via the first crane connection point will cause the lever arm to pivot about the pivot point from the first position to the second position.