Specifications

M
AINTENANCE AND
T
ROUBLESHOOTING
748410-A
August 1999
27
Chemiluminescense Detector Analyzer Module
Rosemount Analytical NGA 2000
4
WARNING: ELECTRICAL SHOCK HAZARD
Disconnect power to the module(s) prior to replacing components.
This equipment should not be adjusted or repaired by anyone except properly
qualified service personnel.
4.1 OVERVIEW
The CLD Analyzer Module requires very little maintenance during normal operation.
Occasionally, the intake fan screen may require cleaning, refer to Section 4.3.
Also, the detector's reaction chamber and sapphire window may require cleaning, refer to
Section 4.7.
White crystal deposits on the windows of the reaction chamber and plugging of capillaries
and vent are usually due to sample contaminates such as ammonia reacting with the high
ozone levels and NO components. To eliminate the contaminates, the sampling system
should be reworked or a preventive maintenance program developed (if dropout is not
excessive). Another source of crystalline formation is contaminated air.
Several components may require replacement. These are discussed in the following
sections.
4.2 F
USES
The main power fuse may require replacement.
Before replacing the fuse, remove power to the Analyzer Module.
See Figure 1-2 for the location of the Power Supply Board main power fuse, which protects
24 VDC input to the module.
NOTE