Michell Instruments XTP601, Руководство пользователя

Страница: 30 / 64

XTP601 User’s Manual
22 97313 Issue 5, May 2018
CALIBRATION
3 CALIBRATION
Factory Calibration :
The unit is factory calibrated at 5 points to maximize the accuracy over the desired
range. The calibration generally includes Zero & Span points as well as 3 intermediate
points. In the case of suppressed zero ranges then the lowest concentration will replace
the Zero Point.
NOTE: Analyzers are calibrated in background gas suitable for the specific
application. Customer's calibration gases must match the process gas. Please
refer to Test Result Sheet or a Michell Instruments' representative
Field Calibration :
Like all process analyzers, the XTP601 will require periodic calibration. The frequency
entirely depends on the location, application and accuracy requirements of the user. The
typical calibration period is expected to be between 1 and 3 months with a Zero gas and
a Span calibration on a monthly basis. The user should establish a calibration frequency
to ensure that the reading is within the specifications required for the process.
NOTE: It is possible to switch off the Field Calibration and revert to the Factory
Calibration. This can be useful for diagnostic purposes if the reading is not
what is expected. The unit is delivered with a factory calibration and, as such,
would not have any field calibration data. As soon as the first field calibration
is performed, the field calibration setting is automatically switched on.
Preparation :
Go to Settings Page (see Section 2.7.1) and make a note of ON/OFF options for all
settings. Re-set these options after calibration.
Zero and Span gas cylinders with correct regulation and flow control should be in place
before installing and powering up the analyzer. Commissioning should include a check
with both gases and, if necessary, a field calibration performed.
All analyzers will be calibrated with an inlet pressure of 1 barg (14 psig) with an
atmospheric vent and flow rate of 300 ml/min (0.63 scfh). The calibration gas applied
to the analyzer should be at the same pressure and flow rate as the process gas being
sampled.
Sample Inlet Pressure:
• 0 to 4 barg (0 to 58 psig)
Sample Flow Rate:
GP1 & GP3 models: 100 to 500 ml/min (0.2 to 1.06 scfh)
EX1, EX3 & GP2 Models: 270 to 330ml/min (0.54 to 0.66 scfh)
There are 2 types of field calibration available.