Vaisala CL31 - Page 124

USER'S GUIDE____________________________________________________________________
122 _________________________________________________________________ M210482EN-D
2. Disconnect the battery, transmitter, receiver, and data cables (refer
to numbers 3, 4, 8, 10 and 16 in Figure 22 on page 104) from the
CLE321 board.
3. To rem
ove the Optics Unit (refer to number 9 in Figure 22), first
remove the holder plate by loosening the four Allen screws on its
front cover.
4.
Detach the internal heater connector and holding the cable aside,
carefully pull out the Optics Unit upper end first.
NOTE
Do not touch the lens of the Optics Unit.
5. Detach the CLM311 twisted pair cable (refer to number 15 in
Figure 22) from the CLE321 board.
6. To detach th
e transmitter, loosen the transmitter ring by turning it
to the right. If necessary, you can use the Allen key as a lever.
Remove the transmitter from the Optics unit.
7. Detach the Laser Monitor Board CLM311 by loosening the two
screws. You can access the screws through the hole in the
transmitter ring (see number 5 in Figure 3 on page 20).
8.
W
rite down the sensitivity value of the old, defective board, for
example, 102 % . If no value is written on the CLM311, use the
standard value 100 %.
9. Write down the sensitivity value of the new CLM311 board, for
example, 98 %. If there is no value on the CLM311, use the
standard value 100 %.
10. Attach the new CLM311 board into the Optics unit and tighten the
two screws.
11. Place the transmitter to its place and tighten the transmitter ring in
such a way that the labels of the transmitter face the measurement
unit door.
12. Attach the CLM311 twisted pair cable to the CLE321 board.
13. Slide the Optics Unit to its place with the bottom end first. Make
sure that no cables get stuck between the optics tube and other
ceilometer components.
14. Snap the internal heater connector to its place.
15. Place all heater cables behind the holder and tighten the four holder
screws.
16. Reconnect the battery, transmitter, receiver, and data cables to the
CLE321 board.
17. Connect the power cable to connector J2 and the maintenance
terminal to CL31.