Table 11-2: Test Functions - Possible Causes For Out-Of-Range Values - Teledyne t100 Operation Manual

Troubleshooting & Service
Sample Pressure measurements are represented in terms of absolute
Note
pressure because this is the least ambiguous method reporting gas pressure.
Absolute atmospheric pressure is about 29.92 in-Hg-A at sea level.
decreases about 1 in-Hg per 1000 ft gain in altitude. A variety of factors
such as air conditioning systems, passing storms, and air temperature, can
also cause changes in the absolute atmospheric pressure.
Table 11-2: Test Functions - Possible Causes for Out-Of-Range Values
TEST FUNCTION NOMINAL VALUE(S)
≤1 ppb with Zero Air
STABIL
SAMPLE FL
650 cm
-20 TO 150 mV with
PMT
0-5000 mV, 0-20,000 ppb
NORM PMT
@ Span Gas Concentration
UV LAMP SIGNAL
2000 - 4000 mV
LAMP RATIO
STR LGT
≤ 100 ppb / Zero Air
DRK PMT
-50 to +200 mV
DRK LMP
-50 to +200 mV
≈ 400 V to 900 V
HVPS
RCELL TEMP
BOX TEMP
PMT TEMP
7ºC ± 2ºC Constant
IZS TEMP (option)
PRESS
SLOPE
OFFSET
TIME OF DAY
224
Faults that cause high stability values are: pneumatic leak; low or very unstable UV lamp
output; light leak; faulty HVPS; defective preamp board; aging detectors; PMT recently
exposed to room light; dirty/contaminated reaction cell.
Faults are caused due to: clogged critical flow orifice; pneumatic leak; faulty flow sensor;
3
/min ± 10%
sample line flow restriction.
High or noisy readings could be due to: calibration error; pneumatic leak; excessive
background light; aging UV filter; low UV lamp output; PMT recently exposed to room
light; light leak in reaction cell; reaction cell contaminated HVPS problem.
Zero Air
It takes 24-48 hours for the PMT exposed to ambient light levels to adapt to dim light.
Noisy Norm PMT value (assuming unchanging SO
Calibration error; HVPS problem; PMT problem.
This is the instantaneous reading of the UV lamp intensity. Low UV lamp intensity could
be due to: aging UV lamp; UV lamp position out of alignment; faulty lamp transformer;
aging or faulty UV detector; UV detector needs adjusting; dirty optical components.
Intensity lower than 600 mV will cause UV LAMP WARNING. Most likely cause is a UV
lamp in need of replacement.
The current output of the UV reference detector divided by the reading stored in the
CPU's memory from the last time a UV Lamp calibration was performed. Out of range
30 TO 120% lamp ratio could be due to: malfunctioning UV lamp; UV lamp position out of alignment;
faulty lamp transformer; aging or faulty UV detector; dirty optical components; pin holes or
scratches in the UV optical filters; light leaks.
High stray light could be caused by: aging UV filter; contaminated reaction cell; light leak;
pneumatic leak.
High dark PMT reading could be due to: light leak; shutter not closing completely; high
pmt temperature; high electronic offset.
High dark UV detector could be caused by: light leak; shutter not closing completely; high
electronic offset.
Incorrect HVPS reading could be caused by; HVPS broken; preamp board circuit
problems.
Incorrect temperature reading could be caused by: malfunctioning heater; relay board
50ºC ± 1ºC
communication (I
Ambient Incorrect temperature reading could be caused by: Environment out of temperature
+ ≈ 5ºC
operating range; broken thermistor; runaway heater
Incorrect temperature reading could be caused by: TEC cooling circuit broken; High
chassis temperature; 12V power supply
Malfunctioning heater; relay board communication (I
50ºC ± 1ºC
Ambient Incorrect sample gas pressure could be due to: pneumatic leak; malfunctioning valve;
± 2 IN-HG-A malfunctioning pump; clogged flow orifices; sample inlet overpressure; faulty pressure sensor
Slope out of range could be due to: poor calibration quality; span gas concentration
1.0 ± 0.3
incorrect; leaks; UV Lamp output decay.
High offset could be due to: incorrect span gas concentration/contaminated zero air/leak; low-
< 250 mV
level calibration off; light leak; aging UV filter; contaminated reaction cell; pneumatic leak.
Incorrect Time could be caused by: Internal clock drifting; move across time zones;
Current Time
daylight savings time?
Teledyne API - T100 UV Fluorescence SO
POSSIBLE CAUSE(S)
2
C bus); relay burnt out
Analyzer
2
concentration of sample gas):
2
2
C bus); relay burnt out
06807F DCN7335
It