Sea-Bird Scientific SUNA V2, User Manual

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Section 9 Troubleshooting
W A R N I N G
Nitrate sensors use an ultraviolet (UV) light. Do not look directly at a UV light when it is
on. It can cause damage to the eyes. Keep products that have UV light away from
children, pets, and other living organisms. Wear polycarbonate UV-resistant safety
glasses to protect the eyes when a UV light is on.
Table 4 General
Possible problem Possible solution
Sensor does not appear to be on Make sure that the cable is connected and the power source is on.
Turn the sensor off for at least 60 seconds. Turn the power on again. If the sensor still
does not appear to be on, use a different cable.
Make sure that the voltage supplied to the sensor is between 8–15 VDC with at least
1 amp of current. Check the cable voltage: put the leads of a DMM in DC voltage mode at
contacts 1 (+) and 2 (-) of the cable to see if there is voltage. If not, use a different cable.
Make sure of the mode of operation. The sensor may be in an unknown mode. Start a
terminal program, supply power to the sensor, and type "$" then "Enter" three or more
times. A prompt from the sensor shows.
Verify the continuity of the cable. Refer to the sensor specifications for connector
functions.
Verify the power consumption. Use a power supply with an accurate digital current
indicator.
• current > 500 mA at 12V: sensor is in data collection mode. Put a piece of white
paper into the optical area and make sure that there is a blue spot. If there is not, the
sensor may be in an unknown mode or there is a system failure.
• current > 5 mA: sensor is in "standby" mode and gives a result over the RS232 input.
• current >100 µA: sensor is not in operation. Contact Customer Support.
Table 5 Operations
Possible problem Possible solution
Self-test fails for internal
humidity Monitor the sensor and do a sensor self-test at regular intervals. Make sure that the
sensor is not attached to any frame so tightly that the pressure housing is out-of-round.
Self-test fails for low spectrum
average or high dark counts Clean the optical windows with a low-lint swab or tissue and isopropyl alcohol.
The average value in DI water is within specifications shown below.
• Dark spectrum: 500–1000 counts, with a standard deviation of no more than
12 counts.
• Maximum light spectrum: no more than 55000, with no more than 60-count standard
deviation.
• Average light spectrum: approximately 10000–15000 counts, with ranges to at least
20000 counts. An average value of <10000 may mean that the optical windows are
dirty or stained, or that the lamp is degraded.
Baseline "drift" Look to see if the lamp is degraded. Apply drift corrections if the rate is approximately
0.004 mgN/L per hour of lamp "on" time.
Wiper does not operate correctly •
Make sure that there is a check in the box for "Integrated Wiper Enabled" in the
General tab of the Settings tab of the software.
• Verify the alignment of the wiper brushes and make sure that the wiper is not bent.
• If the wiper is from another manufacturer, check that the battery contacts are
functional.
• Contact Customer Support for further help.
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