Siemens SITRANS SL Información Del Producto página 3

Step 6: Purging with nitrogen
To make sure that the instrument was purged well all the time during the verification procedure another purging procedure
with nitrogen is necessary. To do so:
1. Attach your nitrogen source to the remaining needle valve once more.
2. Purge the verification tube for about 5 minutes until the concentration value falls well below 0.2 vol % O
overpressure at the inlet does not exceed 1 bar compared to ambient pressure. The gas flow should exceed 1 l/min.
If the O concentration value does not fall below 0.2 vol % O
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behind the lenses during verification. The verification procedure should be repeated from the start.
3. Close the needle valve. Wait for 10 minutes. After this time the O
more than 0.15 vol % O
4. Note this value in the verification sheet.
Troubleshooting: Insufficient purging
The last paragraph of this section is modified to read as follows:
If you are permitted to open the lids, you should first open the lids such that the gas can easily enter the gap between lid and
housing, but without risk of the lids falling off. Then turn on the nitrogen flow. After 15 minutes of nitrogen purging the
housing should be free of oxygen. After purging first close the lids. Then turn off the nitrogen and wait for another 10
minutes. If the oxygen value remains below 0.15 vol %, the problem is solved. If not, repeat the procedure.
Section 11.1
Of the technical data the part Purging - Sensor purging is modified to read as follows:
Purging
Sensor purging
Max. overpressure in the sensor
•
Max. overpressure at sensor purging inlet
•
Purging gas temperature on sensor side
•
Flow
•
Siemens AG
Digital Industries
Postfach 48 48
90026 NÜRNBERG
GERMANY
Amendment 2 to Operating Instructions SITRANS SL Version 04 Amendment 2 to Operating Instructions SITRANS SL Version 04
A5E47707441A, 07/2019
A5E47707441A-01, 07/2019
.
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it is obvious that too much oxygen has entered the volume
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concentration value should not have increased to
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500 hPa
1 bar (100 kPa) above ambient pressure
0 ... +55 °C (32 ... 131 °F)
O application:
2
After commissioning of a sensor enclosure previously filled with air:
min. 1 l/min (for at least 15 minutes),
thereafter: min. 0.25 l/minute
. Make sure the
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