Servicing
PMT Voltage Adjustment
Thermo Fisher Scientific
Model 42
i
Trace Level Instruction Manual
7-19
5.
Remove the four screws securing the power supply to the bracket and
remove the power supply.
Figure 7–9.
Replacing the PMT HVPS
6.
To install the power supply, follow the previous steps in reverse.
7.
Recalibrate the instrument. Refer to the calibration procedures in the
“
Calibration
” chapter.
Use the following procedure to adjust the PMT voltage after switching
from standard to extended ranges or vice versa.
WARNING
The service procedures in this manual are restricted to qualified
service representatives.
▲
1.
Select the NO, NO
2
, and NO
x
ranges. Refer to “Range Menu” in the
“
Operation
” chapter.
PMT Voltage
Adjustment
Assembly Bracket
HVPS
Input Box Screws (2)
Assembly Bracket Screws (2)
Input Box Assembly