Teledyne 6400EH - Sulfur Dioxide Analyzer - Manual (Page 48)

Maintenance Model 6400EH
Teledyne Analytical Instruments 36
TEST
FUNCTION
IDAS
FUNCTION
CONDITION
BEHAVIOR
EXPECTED ACTUAL
INTERPRETATION
SAMP FL SMPFLW
Standard
Operation
Stable
Slowly
Decreasing
• Flow path is clogging up.
- Check critical flow
orifice & sintered filter.
- Replace particulate
filter
DRK PMT DRKPMT
PMT output
when UV Lamp
shutter closed Constant within
±20 of check-
out value
Significantly
increasing
• PMT cooler failure
• Shutter Failure
SO2
Concentration
CONC1
Standard
configuration at
span stable for
constant
concentration
Decreasing
over time
• Drift of instrument
response; UV Lamp
output is excessively
low.
Fluctuating • Leak in gas flow path.
LAMP RATIO LAMPR
Standard
Operation Stable and near
100%
Fluctuating
or Slowly
increasing
• UV detector wearing out
• UV source Filter
developing pin holes
Slowly
deceasing
• UV detector wearing out
• Opaque oxides building
up on UV source Filter
• UV lamp aging