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 149 of 192. (i) within Range : The selection of depths must include O.Sm to full range, in steps of at most 2S% F.S., e.g. a 20m probE! should be tested at 0.S,S,10,lS,20mi (ii) outside Range : Check the probe specifications to find the allowable "ovel'pressure" - the depth to which the probe can be placed without affecting it's calibration. (Note that the probe will be less accurate outside its' calibration range and that water pressure is approximately 10 kPa per metre depth.) since it is possible that the calibration may be affected by going outside i:he specified linear range (even while remaining within the specified allowable overpressure) this stage of the test must include some readings from within the normal operating rang'3. The selection of depths must include o.sm, SO% F'S, and at least 2 depths outside FS, probably 2S% and SO% above FS. (eg. for a 20m transducer, use 0.5, 10, 2S and 30m). If the logging system allows, performance can monitored while logging, and the overrange the transducer's maxinn:m depth set when the errors have become unacceptable. (NotE) that the acceptable error for over-range operation will be much greater than that for normal operation, because the transducer will presumably only be over-ranged accidently and for short periods from which data may be important (e.g. in first few minutes of recovery after a pump test). The downhole equipment must be set up as follOl"s : The transducer is attached to a measuring tape ,'lith the 2:ero mark at the bottom of the transducer (electric insulation tape is adequate). The probe is moved through the water I and held at a particular depth only by the measuring tape. It is desirable that the measuring tape be attached only