Vaisala AWS330 User Manual
Page 189
Chapter 6 ______________________________________________________________ Maintenance
VAISALA ______________________________________________________________________ 187
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 outward.
5.
Loosen the spacer screws with a 7-mm tool and disconnect the
heating element outlet.
6.
Remove the printed circuit board.
CAUTION
Do not twist or bend the connector. This may break the pins.
7.
Loosen the fixing screw of the code disc with an Allen key 2 mm
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 downward through the upper body.
13. Remove the top bearing.
To reassemble the sensor, reverse the earlier work order:
1.
Take the previous steps in reverse order until assembling the code
disc.
NOTE
Be careful when handling the new ball bearings. Do not drop them or
force them onto the shaft.
2.
Attach the code disc (number 7 in Figure 112 on page 189) 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
Make sure that the code disc does not touch the opto-coupler.
3.
Attach the heating element outlet to the printed circuit board. Put
the printed circuit board in place and fasten it with spacers (5).
4.
Put the lower body assembly (4) carefully into place. Fasten the
three screws (3) at the bottom of the sensor. Make sure that the
bigger O-ring (14) is correctly positioned between the upper and
the lower sensor bodies. Check also that the connector O-ring (14)
is in place. It is recommended that you replace the O-ring with a
new one after each opening.