Teledyne 6200T - Sulfides Analyzer - Manual (Page 243)

6200T Total Sulfur Analyzer Troubleshooting
Teledyen Analytical Instruments 243
TEST FUNCTION NOMINAL VALUE(S) POSSIBLE CAUSE(S)
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?
12.1.3. Using the Diagnostic Signal I/O Functions
The signal I/O parameters found under the diagnostics (DIAG) menu combined with a
thorough understanding of the instrument’s principles of operation (refer to Section 13)
are useful for troubleshooting in three ways:
 The technician can view the raw, unprocessed signal level of the analyzer’s
critical inputs and outputs.
 All of the components and functions that are normally under instrument
control can be manually changed.
 Analog and digital output signals can be manually controlled.
This allows a user to systematically observe the effect of these functions on the
operation of the analyzer.
Figure 12-2 shows an example of how to use the signal I/O menu to view the raw
voltage of an input signal or to control the state of an output voltage or control signal.
The specific parameter will vary depending on the situation. Please note that the
analyzer will freeze its concentration output while in the diagnostic signal I/O menu.
This is because manually changing I/O outputs can invalidate the instrument reading.