5.5 Altering Deposition Times
The default deposition time of 60 seconds is suitable for all analysis down to 5
ppb for most elements, 10 ppb for arsenic. To increase the accuracy for the
lower levels, an increased deposition time is recommended. If the user
expects the analysis to be higher, then a shorter deposition time should be
used.
When using the instrument directly, this can be adjusted by choosing a
deposition time, when prompted at the beginning of the test methods. 30, 60
or 120 seconds can be selected by moving the joystick to the right or left on
the screen and pressing the centre of the joystick to ‘OK’ it.
The table below shows the suggested ranges for choosing deposition times.
Deposition Time
Concentration Range
30 seconds
50-500 ppb
60 seconds
10-50 ppb
120 seconds
<10 ppb
The instrument has been designed to have a maximum reading of 500 ppb.
Should the user wish to measure higher than this, they will need to dilute the
sample. For example, if the used wishes to measure 600 ppb, dilute the
sample by half and then multiply the result by 2.
Always dilute with water that will not contribute to the heavy metals being
tested; deionised water is ideal.
Metalyser® Field Pro HM3000 Instruction Manual v 5.0
www.trace2o.com
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