Discharge - tracer (Sommer MFT-2)

Parameter to be measured:

tracer concentration (, discharge)

Method:

in-situ fluorometry

Equipment:

• main device (built-in battery and logger)
• 2 optical probes with 20-m-fibre cables
• precision pipette
• auxiliary bottles and ropes
• power supply
• data cable and software

Advantages:

• no water samples to take, complete data collection on-site
• convenient menu-guided in-situ calibration
• immediate computation of discharge
• can be equipped with alternative filters (not included) to allow detection of other tracers
• also available with two additional conductivity probes (MKT-2)
• sturdy metal transport cases

Disadvantages:

• bulky, minimum setup comprises two large cases
• incomplete manual (How can the clock be set? What exactly does "RAM for 10000 measurements" mean?)
• small internal memory
• awkward software in vintage look and feel
• needs RS 232 (COM-Port) for data download

What to watch out for:

• signal intensity over 2394 (corresponding to concentrations above 310,5 µg/L in de-ionized water) do not yield a linear response any more (oversaturation). Concentrations in de-ionized water above 333,5 µg/L are displayed and logged as 2464. However, these detection limits seem to be lower by factor 3 in natural water (J.B.)
• memory runs as ring buffer and overwrites without asking
• included pipette works with two "pressure points"
• when erasing of logger memory fails or logger readout takes hours, replacing the internal Li-battery and RAM chip may help (soldering skills required)
• avoid uninformed spectators when injecting the tracer, it usually looks quite nasty

Price:

~ 24000 € (2009, Germany)

Links

Product website

Projects that used the above equipment:

Other related web sites: Discharge - comparison of measurements (C2, Flowtracker, Flowsens, ADC, tracer, dipping rod)