M4557 - Model 9210 Nitriding Controller

4.1General Frequency

The Nitriding Sample Cell based analyzer is an extremely stable instrument and requires only very occasional calibration. The exact calibration period depends on the type of sample and environment the instrument is placed in. We recommend that any quality assurance procedures written for the instrument are written to allow verification as opposed to calibration. Verification involves checking that the instrument provides the correct analysis of a standard gas within the limits of the instrument and only calibrating when a result outside of limits is produced. The frequency of the verification would need to be in line with the quality regime being operated by the user.

4.2Calibration method

NOTE: Calibration requires a computer (laptop) with an available serial port and HyperTerminal software.

Introduce the calibration gas in the same way as the normal sample.

The sample cell should be isolated from the process gas and the calibration

gas introduced into the Sensor at the correct flow rate. Note that pressure regulators and gauges that may be in the calibration gas lines all have a certain amount of dead space within them and so may require purging for several minutes before the delivered gas matches that of the cylinder contents. Only when the reading is steady has the dead space been purged.

The recommended order of calibration is:

Zero=xxx.xx<CR><LF>.command where xxx.xx = 0 (See appendix 1) The Zero point will use 100% Nitrogen

Span=xxx.xx<CR><LF>. command where xxx.xx = 100 (See appendix 1) The Span point will use 100% Hydrogen

SSi Manual SERIES 9210-M4557-Nitriding

Page 58 of 58

Page 58
Image 58
SSI America 9210 user manual General Frequency