Teledyne API T802 Paramagnetic O2 Analyzer Operation Manual Troubleshooting and Service

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WARNING
MESSAGE FAULT CONDITION POSSIBLE CAUSES
RELAY BOARD
WARN
The CPU cannot communicate with
the Relay Board.
I2C bus failure
Failed relay board
Loose connectors/wiring
SAMPLE FLOW
WARN
Sample flow rate is < 80 cm3/min or
> 180 cm3/min
Failed sample pump
Blocked sample inlet/gas line
Dirty particulate filter
Leak downstream of critical flow orifice
Failed flow sensor/circuitry
SAMPLE PRES
WARN
Sample Pressure is <15 in-Hg or
> 35 in-Hg
Normally 29.92 in-Hg at sea level
decreasing at 1 in-Hg per 1000 ft of
altitude (with no flow – pump
disconnected).
If sample pressure is < 15in-Hg:
Blocked particulate filter
Blocked sample inlet/gas line
Failed pressure sensor/circuitry
If sample pressure is > 35 in-Hg:
Pressurized sample gas. Install vent
Blocked vent line on pressurized sample/zero/span gas
supply
Bad pressure sensor/circuitry
SYSTEM RESET The computer has rebooted.
This message occurs at power on. If you have not cycled the
power on your instrument:
Failed +5 VDC power,
Fatal error caused software to restart
Loose connector/wiring

11.1.2. FAULT DIAGNOSIS WITH TEST FUNCTIONS

In addition to being useful as predictive diagnostic tools, the test functions

viewable from the front panel can be used to isolate and identify many

operational problems when combined with a thorough understanding of the

analyzer’s theory of operation (see Section 12).

The acceptable ranges for these test functions are listed in the “Nominal Range”

column of the analyzer Final Test and Validation Data Sheet (PN 068350000)

shipped with the instrument. Values outside these acceptable ranges indicate a

failure of one or more of the analyzer’s subsystems. Functions whose values are

still within the acceptable range but have significantly changed from the

measurement recorded on the factory data sheet may also indicate a failure.

Note A worksheet has been provided in Appendix C to assist in recording the

value of these test functions. This worksheet also includes expected values

for the various test functions.

The following table contains some of the more common causes for these values to

be out of range.

07275B DCN6418