Page History

1.

When the User Interface appears (Figure 2), click the dropdown arrow in Currently Viewing Results For field and choose the method for determining MAD values.
Generally, METHOD C (Wet Mass, Dry Mass, and Dry Volume) is used onboard; for a description of methods please review the Methods section in the Moisture and Density User Guide.

2.

Measuring Mass Wet: in the tabular data sheet find the sample to be analyzed and double click the Mass Wet (Figure 3) cell for the particular sample.

3.

A prompt window opens to verify the sample being measured as well as the container number; ensure that both are correct. Further down there is the prompt for the number of mass measurements to be averaged (the general number of measurements is 300; note: if sea state increases increase number of measurements for better accuracy) (Figure 4).

4.

Click Measure. This will bring you to the "measuring window", Expand the measurement window to the desired size.

5.

Balances need to be Tared if they have not been used for over six 6 hours or if anything has changed (e.g., a spill was cleaned up). . Tare the balances with both pans empty. Once the tare is complete, the user can weigh reference masses to ensure the balances are working properly.

6.

Once the balances have been Tared, enter the Reference Mass (the known mass of the reference weight being used). Use a weight similar to the sample + container (20–30 g). It is worthwhile to pay attention to this "weight match" even if it requires several reiterations and restarts of the measurement because it enhances the quality of the data significantly if the reference and unknown balance load is within 5 grams! Place the reference mass on the 'Reference' balance and the sample on the 'Unknown' balance, and click Weigh (Figure 6). Important: Don't touch the reference weights with your hands, use the tweezers.

7.

Once the measurement has been completed and the user is satisfied, click Accept (Figure 7). Note that the Mass Wet field is now populated in the tabular data sheet.

8.

After Mass Wet has been measured, place sample in oven to dry for 24 hr. The samples must be cooled back to room temperature before measuring the dry mass! Leave them in the desiccator for about 3 hours.
Important: Double check the proper operation of the oven and its power plug. Sometimes the power plug can unlock itself and cause an error due to power failure! Of course, an oven also presents high temperature hazards.

9.

After drying the sample, measure the Mass Dry. Double click the Mass Dry column in the correct sample row (Figure 8). Once the sample ID and container number are verified, click Measure. From here repeat steps 5–7 listed above. Make sure to write the data also into a corresponding log sheet (same with data for the drying and pycnometer working steps).