Vaisala LM21 - Page 46

User's Guide ________________________________________________________
46 _____________________________________________________ M210283en-A
Order a spare assembly with the code LM211244 (Cover
Subassembly and Cabling) from Vaisala or its nearest
representative. The spare part contains the front cover with
the hood and face heaters (see Figure 12 on page 47). To
replace the LM211244 subassembly, follow the instructions
below:
1. Disconnect the power from LM21 by disconnecting it
from the power supply.
2. Open the four screws on the cover frame assembly of
LM21.
3. To avoid damaging the calibrator connector inside the
measurement head, gently open the left side (with the
label) of the LMM101 assembly and lift it upwards
pulling out the assembly together with the attached
measurement board. Disconnect the signal and power
cable from the board. See Figure 10 on page 43.
4. Open the three screws holding the LMB201
Measurement board in place. Disconnect the heater and
window contamination connectors and remove the
board. See Figure 12 on page 47.
5. Remove the LM211246 Optics Holding Assembly by
opening the four screws holding it. See Figure 12 on
page 47.