Electrical Alignment - Renishaw ATOM Installation Manual

2. Rotate the disc / hub assembly and observe the maximum and minimum limits of movement
of the alignment band as shown below.
Minimum movement
0° Rotation 90° Rotation
3. Note the axis position at the limits of movement.
4. Rotate the disc so either of these limits of movement is located under the microscope.
5. Gently move the disc relative to the hub in a radial direction so the alignment band moves
half way between the limits of movement.
NOTE: The alignment band is 30 µm wide.
Position of disc at limit of movement of alignment band.
Direction of
movement
6. Rotate the assembly and repeat steps 3-5 until the total alignment band movement is within
the design specifications.
7. Cure the adhesive.
8. Re-check the run-out.
Contact your local Renishaw representative for more information on aligning the disc.
14 ATOM rotary encoder system
Maximum movement
180° Rotation 270° Rotation
Alignment band
Microscope
Position of maximum or
minimum limit of movement
of the alignment band

Electrical alignment

This method involves monitoring the output signals of two readheads mounted 180 degrees apart
and adjusting the disc to minimise the difference in count between the two heads.
NOTE: Due to spacing it is not possible to use this method on discs smaller than 22 mm diameter.
This requires:
• A DSi interface
• 2 × Ri or Ti interfaces
• A digital counter
The clock frequency of the DSi, interfaces and digital counter must be matched to ensure there is
no miscounting. For more information on choosing appropriate DSi and interfaces for your system
contact your local Renishaw representative. For more information on the DSi refer to the TONiC DSi
dual readhead rotary encoder system data sheet (L-9517-9466).
INPUT 1
Customer
DSi
counter
INPUT 2