User`s guide

Chapter 4 ______________________________________________________________ Maintenance
VAISALA______________________________________________________________________ 145
2. Loosen the hex nut of the connector with a 27-mm tool.
3. Loosen the three pan head screws at the bottom of the sensor body
with a 7-mm tool.
4. Remove the lower body assembly by pulling it straight outwards.
5. Loosen the spacer screws with a 7-mm tool and disconnect the
heating element outlet.
6. Remove the printed circuit board.
7. Loosen the fixing screw of the code disc with a 2-mm Allen key
and remove the disc.
8. Remove the external retaining ring (using narrow-pointed pliers).
9. Remove the spacer ring.
10. Remove the internal retaining ring at the bottom of the shaft (using
narrow-pointed pliers).
11. Remove the lower bearing.
12. Push out the shaft downwards through the upper body.
13. Remove the top bearing after pulling out the shaft.
To reassemble the sensor, reverse the above work order. The numbers
in parenthesis refer to Figure 112 on page 147.
1. Take the previous steps in opposite order until assembling the code
disc.
2. Attach the code disc (7) back onto the shaft. The disc has to be
positioned so that it does not touch the opto-coupler on the printed
circuit board (6). Tighten the fixing screw of the code disc.
CAUTION
Be careful not to bend the connector pins.
CAUTION
Do not twist or bend the connector. This may break the pins.
NOTE
Be careful when handling the new ball bearings. Do not drop them or
force them onto the shaft.
CAUTION
Assure that the code disc does not touch the opto-coupler.