Correcting Error Codes; Recommendations For Correct Measurement - Endress+Hauser OXY5500 Operating Instructions Manual

Operating Instructions
Re-install fittings onto probe tip (panel side).
5.
 Ensure plastic ferrules are properly installed.
Route conduit so that probe end (panel side) is aligned with the Tee union.
6.
Insert the probe tip (panel side) into the Tee union.
7.
Connect the conduit bracket with screws (x2) using a 5/32 in. Hex driver.
8.
Connect the conduit clamp with screw using a Philips screwdriver.
9.
Tighten the tube nut on the probe tip (panel side).
10.
Secure the cable gland cap with the adjustable wrench.
11.
 Do not overtighten the cable gland cap.
Close the analyzer enclosure cover and secure with clamps.
12.
Perform a leak test on the analyzer. Refer to Service → .
13.
Calibrate the analyzer. Refer to Calibrating the analyzer → .
14.
8.8

Correcting error codes

If a signal overflow error is received, follow the steps below to resolve the error.
8.8.1 High signal strength: Low O2 or no O2 on OP-3, OP-6, or OP-9 probe
Decrease the LED intensity of the O2 probe by single increments.
1.
Refer to Device settings screen →  for more information on LED Intensity settings.
2.
8.8.2 Low signal strength: High O2 on OP-3, OP-6, or OP-9 probe
Increase the LED intensity of the O2 probe by single increments.
1.
Refer to Device settings screen for more information on LED Intensity settings.
2.
8.9

Recommendations for correct measurement

Calibration of the sensor is recommended before each new application. As an alternative, the calibration values of
the last measurement can be used. If temperature compensation is not used, ensure that the temperature of the
sample is known and is constant during measurement. With temperature compensated measurements, the
temperature sensor Pt100 (RTD probe) should be positioned as close as possible to the oxygen sensor to avoid
temperature differences.
8.9.1 Signal drifts due to oxygen gradients
It is important to remember that the sensor only measures the oxygen content near its surface. The formation of a
bio-film during long-term measurements, or the accumulation of other sample components like oil or solid
substances, may lead to an oxygen gradient.
8.9.2 Signal drifts due to temperature gradients
A further source of imprecise measurement is insufficient temperature compensation. If temperature compensation
is used, ensure that no temperature gradients exist between the oxygen sensor and the temperature sensors. If
measurement is conducted without temperature compensation, bear in mind that the OXY5500 only measures
correctly if the sample temperature is constant during measurement and the temperature is the same as the entry at
the beginning of the measurement. A temperature measurement error of +/-0.3 °C will result in a measurement
error of about +/-1% of reading. The temperature probe provided with the unit has excellent precision, but large gas
temperature gradients will result in an offset between the oxygen probe and temperature probe. To avoid an offset,
ensure that the gas temperature has been stabilized prior to passing over the oxygen probe. SCS systems provided by
Endress+Hauser are designed to ensure that this is not a problem.
82
OXY5500 Gas Analyzer
Endress+Hauser