Renishaw TONiC T20x1 REXM20 Installation Manual page 20

Adjusting the REXM/REXT ring
(full and partial rotation)
1. Remove the protective film from the surface of the ring.
2. Measure the run-out on the ring using a Dial Test Indicator (DTI).
CAUTION: Use a DTI with low exertion force to avoid scratching the ring surface. A DTI with
a ruby ball stylus is recommended as a further precaution against scratches.
NOTE: At this stage the ring is not firmly fixed so, to avoid causing the ring to shift position,
rotate the ring slowly and smoothly.
3. Where the DTI shows the lowest radius reading, gently tap the opposite side of the ring on
the edge using a rubber mallet, until the DTI reading is approximately at the 'mid-point' of
the run-out.
4. Find the new lowest radius reading.
5. Tap the opposite side of the ring with a rubber mallet until the DTI reading is at the 'mid-point'
of the run-out.
6. Repeat this process until the run-out of the ring is approximately 30 µm TIR.
20 TONiC REXM20 / REXT20 angle encoder system installation guide
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