Teledyne 501 TRS, Operation Manual, Page: 68 / 111

TROUBLESHOOTING and REPAIR Teledyne API - T102/501 TRS, Addendum to T101 Operation Manual
66
Table 11-1. Test Functions - Possible Causes for Out-Of-Range Values
ERROR
MESSAGE
CAUSE NOTES
Thermocouple burnt out or wiring between
Thermocouple and Temperature Controller is open.
The controller process value exceeds the upper
input range set point by 5% of full scale.
Controller will automatically turn off the
converter heater and allow the TRS converter
to cool down.
• Check the thermocouple for shorts or
opens.
• Check the condition of the wiring between
the thermocouple and the controller.
When the controller process value is below the
lower input range set point by 5% of full scale.
When either the Upper or lower limit of the
input range is set improperly (e.g. Upper
limit is set to lower value than lower limit).
Controller will turn off heating element until
error is corrected.
Undefined fault in controller
Turn off M501-TRS. Call TAPI Technical Support.
11.1.2.
Fault Diagnosis with Test Functions
The Following table supersedes the Test Functions-Possible Causes for Out-of-Range
Values Table in the
Fault Diagnosis with Test Functions section in the T101 Manual -
PN 07266.
Table 11-2. 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 PMT; PMT
recently exposed to room light; dirty/contaminated reaction cell.
SAMPLE FL
650 cm 3 /min
± 10%
Faults can be caused by: 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; light
leak (improper assembly); aging UV filter; low UV reference output; PMT recently
exposed to room light; light leak in reaction cell; reaction cell contaminated; HVPS
problem.
It takes 24-48 hours for a PMT exposed to ambient light levels to return to normal
functioning.
NORM PMT - -
Noisy Norm PMT value (assuming unchanging SO
2
concentration of sample gas):
Calibration error; HVPS problem; PMT problem; UV reference problem; UV lamp
problem.
UV LAMP 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; dirty optical components.
Intensity lower than 600 mV will cause UV LAMP WARNING.
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 40-100 ppb
High stray light could be caused by: aging UV filter; contaminated reaction cell;
light leak; pneumatic leak.
DRK PMT -50 - +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 - +200 mV
High dark UV detector could be caused by: light leak; shutter not closing
completely; high electronic offset.
07267B DCN6485