Electronic Data Collection and Analysis System
Yin Foo, Des; Foley, Margaret
E-Publications; PublicationNT; E-Books; Report ; 39/1992
1992-08-01
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Date:1992-08
English
Power and Water Authority
Darwin
Report ; 39/1992
application/pdf.
Check within Publication or with content Publisher.
https://hdl.handle.net/10070/229024
https://hdl.handle.net/10070/673447
Technical Report WRD92039 Viewed at 15:07:17 on 29/07/2010 Page 143 of 192. Cl .2 C,l\.LIBRATION METHODS The system is calibrated as a whole, with the transducer attached to the logger. DOImhole calibration: 'rhe transducer is moved through the 'ilater to a series of known depths f as described in section C2. 2 and so is exposed to normal operating water temperature and pressure conditions. See also section Cl.3. reb) Probe connected to pressure control instrument: As per I (a), except that the transducer is not immersed, and is at room temperature. This method ,vas not found to be as accurate a.s Method I(a) because of some difficulties experienced used, and temperature. Ivith the stability of the particular instrument possibly because of calibration drift with Method II : Electric signal generator connected to the logger The signals appropriate to particular depths are obtained from t.he transducer specifications, and applied to the logger input circuit. (The manufacturers must be consulted about any precautions necessary.) This method suffers from the disadvantage that it depends on the probe performing to specification, but may be the only practical method in the case of calibrating for quantities which are difficult to control (e.g. Wind speed). Method HI "Software" calibration In some specifications JllJl_ at 0 depth cases (including Torrens) the probe can be entered directly in the logger and 20 rnA at 10m depth) and the logger output (e.g. 4 software