User guide

96
Pedestal
The additional cables are used to provide increased stiffness and drive redundancy. If a cable becomes damaged during
usage, merely cut off the cable and continue to use the positioner. You can replace the cable at your maintenance
facility whenever time permits.
The cables are sized to last the life of the positioner. No replacement from wear is expected. The springs package at one
end will automatically compensate for any elongation of the cable. At installation, the Belleville springs are collapsed until
no "air" is seen between the springs. You should check this condition yearly to monitor the slow settling of the cable
strands.
Polarization Position Feedback
The polarization position feedback is produced by the optical
encoder mounted on the output shaft on the motor. The
polarization stow and limit switch is mounted under the
polarization platform and is accessible under the pol cover. The
switch is fixed to a plate and is actuated by a rotation cam. The
limits are controlled by using inputs from switches and optical
encoder together and are set in and controlled by the TracStar
controller. Pol stow is achieved by activating the stow switch
mounted on the polarization cam. The polarization drive has the
mechanical capability of ±75° or ±95°.