09419A DCN8342
Teledyne API Model 480L O
3
Monitor User Manual
57
8.2.1 SENSOR OK
The Sensor OK status indicates the status of the O
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sensor module in the monitor.
The normal state of this report in the status area of the display is OK and the output
signal will be open. If this error is triggered, the signal is opened, and the status area
will read ERROR.
The most common cause of this warning is a failure of the UV LED A UV LED
adjustment (Section 7.6) should be attempted. If the UV LED cannot be adjusted to
meet the specified values, then a UV LED replacement should be performed
(Section 7.7).
This warning can also be caused by a communications error with the sensor module.
Inspect the two cables between the Mainboard PCA and Sensor Module for loose or
intermittent connections (See Figure 7-1 for monitor layout). If no cable problem
can be found, then the Sensor Module should be replaced.
8.2.2 INVALID READING
The Invalid Reading status area indicates that the instrument is reading a value that
cannot be represented properly on the analog output. Since the analog output is
limited to 0-5V (or 4-20mA), it cannot properly represent negative values, or values
in excess of the full-scale range. If this error is triggered, the signal is closed, and
the status area will read ERROR.
If the monitor is consistently reading negative values, then a zero calibration should
be performed, see Section 5.2.3.2.
If the monitor is consistently reading values in excess of the full-scale range, then
the range value should be adjusted higher. See Section 5.2.4.1 for details on setting
the range value.
8.2.3 CHECK LAMP
The Check Lamp status indicates that the UV LED intensity has dropped below
250mV, a level where UV LED adjustment (Section 7.6) should be made at the
next convenient opportunity. Note that this is a non-critical warning and immediate
service is not required. However, if the UV LED intensity drops below 125mV, then
the Sensor OK status will show an ERROR and the monitor must be immediately
serviced (Section 7.7) or taken off-line.
8.2.4 PNEUMATIC ERROR
The Pneumatic Error status indicates that one of the pneumatic parameters, flow or
pressure, has gone outside of normal ranges. Note that this is a non-critical warning
and immediate service is not required. If this error is triggered, the signal is closed,
and the status area will read ERROR. However, if the Sensor OK state changes to
ERROR then the monitor must be immediately serviced or taken offline.
The first step in troubleshooting a Pneumatic Error is determining which parameter
has caused the warning. From the Sensor menu area, view the Flow and Pressure
value, compare them to the allowable limits described in Table 8-1 and take
appropriate action as described below.
