Using The Diagnostic Signal I/O Function - Teledyne T200H User Manual

Troubleshooting & Service
Table 7-1: Test Functions - Possible Causes for Out-Of-Range Values
TEST FUNCTION
NOX STB
SAMPLE FL
OZONE FL
PMT
NORM PMT
AZERO
HVPS
RCELL TEMP
BOX TEMP
PMT TEMP
IZS TEMP (OPTION)
MOLY TEMP
RCEL (PRESSURE)
SAMP (PRESSURE)
NOX SLOPE
NOX OFF
NO SLOPE
NO OFFS
TIME OF DAY

7.1.3. USING THE DIAGNOSTIC SIGNAL I/O FUNCTION

218
INDICATED FAILURE(S)
Unstable concentrations; leaks
Leaks; clogged critical flow orifice
Leaks; clogged critical flow orifice
Calibration off; HVPS problem; no flow (leaks)
AutoZero too high
Leaks; malfunctioning NO/NOx or AutoZero valve; O
HVPS broken; calibration off; preamp board circuit problems
Malfunctioning heater; relay board communication (I
Environment out of temperature operating range; broken thermistor
TEC cooling circuit broken; relay board communication (I
Malfunctioning heater; relay board communication (I
Malfunctioning heater; disconnected or broken thermocouple; relay board communication
2
(I C bus); relay burnt out; incorrect AC voltage configuration
Leak; malfunctioning valve; malfunctioning pump; clogged flow orifices
Leak; malfunctioning valve; malfunctioning pump; clogged flow orifices; sample inlet
overpressure;
HVPS out of range; low-level (hardware) calibration needs adjustment; span gas
concentration incorrect; leaks
Incorrect span gas concentration; low-level calibration off
HVPS out of range; low-level calibration off; span gas concentration incorrect; leaks
Incorrect span gas concentration; low-level calibration off
Internal clock drifting; move across time zones; daylight savings time?
The signal I/O parameters found under the diagnostics (DIAG) menu combined with a
thorough understanding of the instrument's theory of operation (Section 8) 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 to systematically observe the effect of these functions on the operation of
the analyzer. Figure 7-2 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.
Teledyne API - Model T200H/T200M Operation Manual
air filter cartridge exhausted
3
2
C bus); relay burnt out
2
C bus); 12 V power supply
2
C bus); relay burnt out
07270D DCN7141