A&D Weighing BM-20 - Manual (Page 24)

22 BM series
6.3.
Counting Mode (PC)
This is the mode to determine the number of objects in a sample based on the standard sample
unit mass. The unit mass means an average mass of the samples. The smaller the variation in
the samples, the more accurate the count will be. The balance is equipped with the Automatic
Counting Accuracy Improvement (ACAI) function to improve the counting accuracy.
Notes
Use samples with a unit mass of 1 mg or more for counting.
If the sample unit mass variable is too large, it may cause a counting error.
To improve the counting performance, use the ACAI function frequently or divide the samples into
several groups and count each group.
Selecting the counting mode
1 Press the MODE key to select the unit (counting mode).
Storing a sample unit mass (Weighing input mode)
2 Press the RANGE key to enter the sample unit mass storing mode.
3 Select the number of samples using the RANGE key.
It may be set to 10, 25, 50 or 100.
Advise A greater number of samples will yield more accurate
counting result.
4 Place a tare (container) on the weighing pan, if necessary.
Press the RE-ZERO key to cancel the weight (tare).
The number specified in step 3 appears.
Example: 25 0 is displayed if 25 is selected in step 3.
5 Place the number of samples specified on the pan.
In this example, 25 pieces.
6 Wait for the stabilization indicator to be displayed.
Press the PRINT key to calculate and store the unit mass.
Then the balance displays 25 and is set to count samples
with this unit mass. To improve the accuracy of the unit mass,
proceed to step 8.
Notes
If the balance judges that the mass of the samples is too light to
acquire accurate weighing, it displays an error requiring the
addition of more samples to the specified number.
Example:
50 - appears, requiring 25 more samples. Add
25 samples and press the PRINT key. When the unit mass is
stored correctly, the balance proceeds to the counting mode.
If the balance judges that the mass of the samples is too light (under
0.0001g) and can not be stored as the unit mass, it displays lo .
The sample unit mass is stored in non-volatile memory, and is
maintained even if the AC adapter is removed.
Counting Operation
7 Place the samples to be counted on the pan.
Read the result and remove them from the pan.
Weighing pan
Tare
(Container)
25 samples
Place samples
Counting result
To Step 8 when using
the ACAI function.