Finally pH Measuring Systems Have Become Manageable
Endress+Hauser have optimised the performance and productivity of their extensive range of pH electrodes with the introduction of Memobase. This innovative electrode management system builds on Endress+Hauser’s Memosens technology giving users much-needed insight into the reliability, performance, estimated lifetime and early-warning-failure, previously unheard-of in the field of pH measurement.
The introduction of Memosens based pH electrode technology has transformed the way plants maintain and manage pH measurement. It has made process plants safer, more productive and cost efficient. The key innovation to emerge from Memosens’ application to pH measurement is the digitization of the analogue measuring signal directly in the electrode. The ‘smart’ electrode head is now where the actual pH values are determined and digitally transmitted to the transmitter, removing very real pH-offset-error due to the older analogue technology.
Memosens technology makes it possible to pre-calibrate any and all of the online pH electrodes at a central calibration station. Pre-calibration can now be performed in the laboratory or workshop as calibration at the measuring point is no longer necessary. When Memobase is added to this central calibration station, the benefit is that for each pH electrode on site, “an audit trail/database” is stored in a report format on a conventional spreadsheet. This audit trail is a record of all past and current calibration dates, commissioning dates, operating hours and additional electrode information. Operators can now identify early-warning-failure patterns from the line-graph chart that incorporates all historical calibration data, including dates and times of each event.
Recorded information specific to each measuring point can be reviewed (electrode slope degradation) revealing new information regarding that specific online process. For example, the rate at which the pH electrode deteriorates gives information on the process conditions. This information, specific to a particular tag, is recorded and can be printed out in a report by selecting the “Report” icon in the Memobase software.
Regular regeneration and cleaning prolongs the electrode service life by up to 40 per cent and results in longer electrode lifetime due to optimised electrode maintenance. The advantage of pre-calibrated pH electrodes is that process downtime is reduced and the calibration procedure can now be performed by operating staff that do not require any specialised knowledge of measurement technology as no recalibration at the measuring point is needed.
The complete life cycle of the electrode is therefore documented – from commissioning to scrapping. Using this data, measuring systems and maintenance concepts can be analysed and, if necessary, optimised. “The reproducible laboratory conditions enable a more precise calibration and therefore more accurate process management,” says John Immelman, Managing Director, Endress+Hauser Australia.
