Those rules are written more for arenas that aren't designed to take full combat spinners. If a 'spinning' weapon doesn't exceed two of those three criteria it can probably be viewed as a fast electric lifter/hitter than a spinner, though the final call always rests with the EO.

The arenas that beetleweights fight in currently in the UK are all designed for full combat, so there are no restrictions (yet!) on the speed and weight of spinning weapons.

And not quite Harry. Exceeding two of the specified figures rather than the actual rules themselves would require approval. So, for example, a spinning mass bigger than 500mm and going faster than 500RPM would need approval even if it weighed less than 20% of the robot's total weight