User Guide

Teledyne API M100E Analyzer Operation Manual Troubleshooting & Repair
259
Table 12-2: Test Functions - Possible Causes for Out-Of-Range Values
TEST
FUNCTION
NOMINAL VALUE(S) POSSIBLE CAUSE(S)
STABIL
≤1 ppb with Zero Air
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.
SAMPLE FL
650 cm
3
/min ± 10%
Faults are caused due to: clogged critical flow orifice; pneumatic leak; faulty flow sensor;
sample line flow restriction.
PMT
-20 TO 150 mV with Zero
Air
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.
It takes 24-48 hours for the PMT exposed to ambient light levels to adapt to dim light.
NORM PMT
0-5000 mV, 0-20,000 ppb
@ Span Gas
Concentration
Noisy Norm PMT value (assuming unchanging SO
2
concentration of sample gas):
Calibration error; HVPS problem; PMT problem.
UV LAMP
SIGNAL
2000 - 4000 mV
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.
LAMP RATIO
30 TO 120%
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
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.
STR LGT
≤ 100 ppb / Zero Air
High stray light could be caused by: aging UV filter; contaminated reaction cell; light leak;
pneumatic leak.
DRK PMT
-50 to +200 mV
High dark PMT reading could be due to: light leak; shutter not closing completely; high
pmt temperature; high electronic offset.
DRK LMP
-50 to +200 mV
High dark UV detector could be caused by: light leak; shutter not closing completely; high
electronic offset.
HVPS
≈ 400 V to 900 V
Incorrect HVPS reading could be caused by; HVPS broken; preamp board circuit
problems.
RCELL TEMP
50ºC ± 1ºC
Incorrect temperature reading could be caused by: malfunctioning heater; relay board
communication (I
2
C bus); relay burnt out
BOX TEMP
Ambient
+ ≈ 5ºC
Incorrect temperature reading could be caused by: Environment out of temperature
operating range; broken thermistor; runaway heater
PMT TEMP
7ºC ± 2ºC Constant
Incorrect temperature reading could be caused by: TEC cooling circuit broken; High
chassis temperature; 12V power supply
IZS TEMP
(OPTION)
50ºC ± 1ºC
Malfunctioning heater; relay board communication (I
2
C bus); relay burnt out
PRESS
Ambient
± 2 IN-HG-A
Incorrect sample gas pressure could be due to: pneumatic leak; malfunctioning valve;
malfunctioning pump; clogged flow orifices; sample inlet overpressure; faulty pressure
sensor
SLOPE
1.0 ± 0.3
Slope out of range could be due to: poor calibration quality; span gas concentration
incorrect; leaks; UV Lamp output decay.
OFFSET
< 250 mV
High offset could be due to: incorrect span gas concentration/contaminated zero air/leak;
low-level calibration off; light leak; aging UV filter; contaminated reaction cell; pneumatic
leak.
TIME OF DAY
Current Time
Incorrect Time could be caused by: Internal clock drifting; move across time zones;
daylight savings time?
04515F DCN6048