Electronic Data Collection and Analysis System
Yin Foo, Des; Foley, Margaret
E-Publications; PublicationNT; E-Books; Report ; 39/1992
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Power and Water Authority
Report ; 39/1992
Check within Publication or with content Publisher.
Technical Report WRD92039 Viewed at 15:07:17 on 29/07/2010 Page 112 of 192. ,;i : ~LL~.:,;a A ComI!!mJ; The hardware recommendations made above are based on information supplied In manufacturers' brochures and by manufacturers themselves, or their agents. durlng telephone conservations. When it is decided to proceed with the purchase of the abovementioned. or any other. items more detailed inquiries will need to be made to confirm !nfomlaUon and prices supplied herein and to soliCit any other infom1<1tlon required for complete system design prior to purchase. The above recommendations are thus made subject to a favourable outcome to these further mquiries. OTHER CONSIDERATIONS Transducer CAlibration For many loggers. the transducer current or frequency readings are converted to head or drawdown as the data stored in the logger is downloaded; the transducer callbrailon constants (which may vary slightly from transducer to transducer) are stored in a me on the downloading computer. Tn the case of the Mlndata Jogger. I gather that the calibration slope Is assumed Invarlant and the elIect of olfset variation from unit to unit !s allowed for by enquiring of the user the water height (according to any datum) when the transducer is installed; all logger outputs are then appropriately adjusted. In the Westdata case, the transducer can be entJrely re-calibrated each lime It is installed. for both siope and olIset. Transducer callbratlon drift can be monilored by comparing logger output with manually measured water depths. [n fact if this latter infomlation is taken while a pump test is underway. then the tr:msducer can be calibrated agall1Sl drawdown in the course of each pump test. Hence an operator procedure that allows for the measurement of water levels in all bores before a pumptest begins. then Just before the pump is switched off and again Just before the transducers are removed from the hole. will provide enough information to ensure that, proVided 'Jansducer linearity is accordlng to specifications. the logger-recorded water levels are correct in spite of any possible drift In the transducer calibration constants over time, Naturally. the facility for using manually-gathered water levels for such continuous transducer calibration will need to be built lnto the software. It may bc of interest ':0 PA\VA statf to know that the ACTFR has a transducer callbration lacllity for water depths of up to 10 metres. This has been found useful In monitorlog transducer and logger performance as well as in checking ilnearlty specifications. 49 I II it iI ii i
Aboriginal and Torres Strait Islander people are advised that this website may contain the names, voices and images of people who have died, as well as other culturally sensitive content. Please be aware that some collection items may use outdated phrases or words which reflect the attitude of the creator at the time, and are now considered offensive.
We use temporary cookies on this site to provide functionality.
You are welcome to provide further information or feedback about this item by emailing TerritoryStories@nt.gov.au