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Old 10th Apr 2019, 01:37
  #3776 (permalink)  
Loose rivets
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DaveReidUK #3825 Showed a clear picture of the screwjack motor but presumably not the gearboxes and clutches.

Apropos it having a 'continuous rating' or not, judging by the size of the code plate, it's not an extraordinarily large unit though the 3 phase supply is an indication of its power.

It was stated somewhere that there's one motor, and the clutches and gears are selected for the differing modes. More dredging memories. One statement said the motor can keep running while functions change - implying there might be a time where neither clutch was engaged. I would assume a time-out, on the running, but have failed to find positive details of the processes. I read the very detailed modes with relay control etc., but not how that motor operates inside. i.e., there must be a huge reduction even prior to the other gears/clutches. I base this on the shaft size.

The point has been raised, but the hammering that system got, i.e. heaving against stalled (as in mechanically stalled) stabilizer, might just have made those inert last moments come about by failure rather than just the excessive (aerodynamic) loads.
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