
Service and maintenance
9.1 Instrument verification
SITRANS SL
Operating Instructions, 12/2010, A5E01132948-04
159
Step 3: Verification
1.
Watch or record the measured value for at least 20 seconds to ensure that it is stable (i.
e. concentration varies not more than ±1 vol % of the reading).
2.
Take 5 successive concentration values and write them into the verification sheet.
3.
If the difference between the highest and the lowest concentration value is more than
1 %, the measurements must be repeated.
4.
Compare the average of the 5 values with the verification set point stated in the
certificate. If it lies within the range between the set point and the total verification
uncertainty, the instrument works properly.
If the average value lies outside this range, repeat the verification procedure. If the test
still fails, contact Siemens support providing the filled-out verification sheet will all
verification results.
See also
Verification Sheets (Page 198)
9.1.3
Verification of systems used in hazardous areas
Verification setup
Verifying the system requires that it is mounted to the verification module.
WARNING
If the verification is to be carried out in the hazardous area be sure to confirm with the
plant manager that it is safe to do so (hot work permit)!
The thermometer is neither ATEX nor FM certified. If the thermometer therefore must be
removed, the hole where the thermometer was attached should be plugged and the
temperature measured with some other device.
Note
The verification kit is not part of the standard delivery. If you carry out the calibration
verification for your own, you have to order the verification kit additionally.
Procedure
1.
The sensor and transmitter have to be dismounted from the measuring setup.
2.
If necessary the cables in the receiver and the transmitter have to be disconnected. The
units have then to be moved to an appropriate location for verification. The sensors must
then be reconnected to each other using a sensor connection cable.
3.
Verify the system as described in sections before.
4.
Reinstall in reverse order.