HF scientific MicroTPI Field Portable Turbidimeter (Old) - Manual (Page 9)

3.0 Normal Operation
This instrument allows you to measure the turbidity of a grab sample. The turbidity is
reported in Nephelometric Turbidity Units (NTU). Readings above 1100 NTU are
outside the range of this instrument.
During normal operation, the instrument will have the last valid turbidity reading
indicated on the display (see illustration below).
If the sample that you are measuring has a turbidity that is higher than that which the
instrument can measure, the instrument will indicate this as an over-range condition:
In certain instances, during normal operation, the instrument will briefly display a row of
dashes across the display
This indicates that either the instrument is performing an auto-ranging function, or the
sample has a substantial amount of bubbles. If the dashes remain for an extended period
of time please ensure that the sample does not have a large amount of bubbles present; if
there are not bubbles present, please contact the Technical Services Department for
further assistance and guidance (refer to section 5.3).
3.1 Routine Measurement
The instrument measures and reports the turbidity of a sample in nephelometric turbidity
units (NTU’s).
Note: Nephelometric turbidity units (NTU’s) are numerically equivalent to Formazin
turbidity units (FTU’s) (See Glossary).
Ref. 22666 (12/04)
Rev. 1.4
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