Tt calibration example – ETS-Lindgren 2081 Turntable Manual (Series 2081-2.0, 2081-2.5, 2081-3.0, 2081-4.0, 2081-5.0, 2081-6.0) - (Archived) User Manual

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MODEL 2081 TURNTABLE SERIES

Operation

REV D – PN 399212

2. Insure that the turntable is positioned to allow more than a full

revolution of travel in the clockwise direction and use the
STEP keys to run the turntable clockwise a few degrees to
remove any play in the table.

3. Mark the current location of the turntable against the ground

ring (masking tape works well), and set the current position
reading to 000.0.

4. Using the STEP keys, rotate the turntable clockwise until it is

again aligned with the mark on the ground ring. For best
results, the last motion should always be in the clockwise
direction to insure that any play in the gearing between the
motor and encoder is accounted for.

5. Record the reading of the display, ignoring the decimal point

(i.e. 360.0 would be 3600). This is the encoder calibration
value. NOTE: If the value is below 3600, the resolution of the
encoder is low and thus the 2090 will not provide 0.1 degree
resolution, even though the display shows that digit. If the
value has gone past 9999, the encoder has too many counts per
meter and the 2090 can not correct for it. In this case, contact
ETS-Lindgren for assistance.

6. Enter this value for the encoder calibration value and reset the

limits and position information.

7. Test the turntable by moving it a complete revolution and

comparing the alignment marks. It may be necessary to adjust
the encoder calibration value up or down slightly depending on
the result. NOTE: When scanning between limits, it is not
uncommon to have a small discrepancy between the absolute
position of the table and the display on the 2090. This is
because reversing the direction of rotation reverses any gear
play between the encoder and the table top, allowing that play
to be visible in the positioning accuracy.

TT CALIBRATION EXAMPLE

The table is set at the 0 degree position. A piece of tape is placed
on the edge of the TT to line up with the edge of the gearbox
cover. The table is stopped when the tape travels exactly 360

Archived 3/18/10