[TowerTalk] Tailtwister Problem

[Ed Gray]

I did not properly explain my test setup.  One winding is not floating,
thinking DC not AC sorry!  Anyway the AC capacitor is across the leads
going to each winding and the 28 VAC is feeding to each winding, one thru
the capacitor and the other direct and ground from the supply to ground
where the two motor windings are tied together to ground on the other end.
This would be as per how I read the diagram for the tailtwister.  I did not
describe it accurately.

Here is a test procedure I have used before to eliminate/isolate a lot of
possible problems.  It is for a test bench with the rotor tore apart.
Remove the top and bottom bell housings.  Unsolder the motor leads going to
each field from the right and left limit switches.  If I remember correctly
CCW is on the left limit switch and CW is on the right limit switch.  I
don't have the diagram in front of me.  Put an extra AC capacitor of the
proper rating across the two leads going to the windings.  The cable to the
rotor is not hooked up.  Hook 3 or 4 foot of wire from terminal #1 ground,
from the control box to the ground lead, typically black from the motor
which is grounded to the rotor case.  Hook a wire from terminal #2  of the
rotor control box which has aproximately 26-28 VAC on it when you depress
the brake release lever.  Hook this lead directly to the winding that was
hooked to the left limit switch and the motor turns CCW when you apply
28VAC.  Hook this lead to the winding that was hooked to the right limit
switch and the motor turns CW when you apply 28 VAC.  This way you can see
what is going on with all the gears.  Obviously the limit switches and
rotation indication will not work.  CAUTION don't rotate into the stop
lever.  This eliminates cable problems, connection problems, solder joint
problems and limit switch problems and puts the AC start capacitor right at
the motor which is what I do with all my TAILTWISTER's IS TO PUT A high
quality AC capacitor on the tower right by the rotor.  It also elimates the
need for 8 wires.  I use # 12 UF for my main leads and parallel the extra
leads.

The reason I mention rotating into the stop is I caused a problem with a
Tailtwister once by releasing the brake when the rotor was near the stop
and the wind took the rotor into the stop and bent the stop arm and in the
process stripped one of the small gears that drives the ring gear.  I would
think one should not be able to do this with just the motor but I have not
tried that!  But with a big array with lots of wind surface and lots of
wind the result is major damage!   LESSON learned do not try and move a big
array in the wind near the stop.  
 73 Ed W0SD

Ed Gray McCook County Extension Educator-Marketing/Farm Management 
Box 130
130 East Essex
Salem, SD 57058-0130

Office phone 605 425 2242
FAX             605 425 3144


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