FAQ bbe 10cells

The cell count measured by the bbe 10cells is calculated using the following equation:

Cell count = Signal × Cell Factor

The typical Cell Factor is approximately 550.

To determine a sample-specific Cell Factor, use a sample for which the actual cell count is already known. Perform a measurement with the bbe 10cells. Several replicate measurements are recommended to account for statistical variation. The correction can then be calculated as follows:

Correction Factor = Known Cell Count / Measured Cell Count

The new Cell Factor is calculated by:

New Cell Factor = Existing Cell Factor × Correction Factor

Enter the resulting New Cell Factor in the Settings tab of the bbe 10cells.

A subsequent test measurement should then produce a cell-count value corresponding to the known cell count of the reference sample.

The bbe 10cells 3 (2020 model) has a built-in UN3841 battery pack.

The battery specifications are:

• Battery capacity: 28.9 Wh
• Number of batteries: 3
• Battery: Built into the instrument

The Cell Factor is a user-adjustable factor that directly influences the measurement result. It is set to 100 by bbe when the instrument is delivered. The value can be understood as a percentage:

• 100 = 100% of the measured value
• 200 = twice the measured value
• 50 = half the measured value

The Cell Factor can be adjusted by the customer via the touchscreen GUI. In addition to the Cell Factor, the instrument contains a hidden Photocounter Factor (Photomultiplier Factor). This factor is determined and fixed by bbe during the calibration of the instrument. The two factors are combined internally to determine the final measurement result. This separation between the factory calibration factor (Photomultiplier Factor) and the user-adjustable Cell Factor is an important difference compared with the TC2. In the 10cells, every instrument is delivered with the same Cell Factor of 100, regardless of the individual variation in the photomultipliers installed in the instruments.

For calibration, bbe uses a fluorescence test emitter (dye). Its fluorescence response is regularly checked against fluorescence measurements from weighted and evenly distributed algae samples applied to a filter. The algae samples are manually counted using fluorescence microscopy and serve as an independent reference for controlling the calibration.

The “+” indicators show the current measurement quality of the sensor. They are based on a continuous background check of the sensor values between measurements.

Before starting a measurement, it is recommended to check that “++” or “+++” is displayed.

• “+++” – Very good measurement quality: The sensor has very low dark counts, resulting in low measurement noise and high resolution. This is particularly important when measuring very low cell concentrations, where high resolution is required.
• “++” – Good measurement quality: The sensor has moderate dark counts. Measurements are still possible, but somewhat higher measurement uncertainty can be expected.
• “+” – Reduced measurement quality: The sensor has elevated dark counts. The 10cells may display a warning when starting a measurement and recommend measuring in a cooler environment. On early prototypes equipped with cooling, the instrument may also recommend activating the cooling.

The quality indicator is strongly influenced by temperature, which is one of the main factors affecting sensor dark counts and therefore measurement quality.

While the flap is open, ambient light can enter the instrument, temporarily increasing the dark counts. In this situation, a display of “+” or, at most, “++” is normal.

After inserting the sample, wait approximately 2–3 seconds before pressing the Start button. This allows the sensor's dark counts to return to their normal range.

Yes, but the suitability depends on the cell concentration. High cell concentrations can generally be measured regardless of whether “+”, “++”, or “+++” is displayed. For low cell concentrations, high measurement resolution is important. Such measurements should preferably be performed only when “+++” is displayed.

The firmware of the 10cells can be updated using a USB flash drive as follows:

1. Format the USB flash drive as FAT32.
2. Copy the firmware file tc3.bin to the USB flash drive.
3. Insert the USB flash drive into the USB port of the 10cells.
4. On the 10cells, select Options → System Info → Firmware Update.
5. Confirm the update by selecting Yes.
6. Wait until the update process has finished. The instrument will restart automatically, and the message “Firmware Update: DONE” will appear after the reboot.
7. Remove the USB flash drive

The PDF report feature is available from firmware version 1.1.0 onwards.

If the 10cells is updated to a firmware version that supports PDF reports but the feature was not previously installed, the PDF template must first be copied to the instrument:

1. Obtain the file tc3-template.pdf.
2. Copy the file to a FAT32-formatted USB flash drive.
3. Insert the USB flash drive into the 10cells.
4. The instrument displays “Importing PDF template from USB”.
5. Wait until this message disappears. The template has then been successfully imported.
6. Enable the PDF report feature in the instrument settings.

From the next measurement onwards, the 10cells can generate a PDF report using the imported template. The instrument copies the template and inserts the measurement data into it.

Yes. The optional “10cells PDF Logo” feature allows a company logo to be included automatically in the PDF reports.

To use this feature:

1. Send the company logo to bbe. An image size of approximately 800 × 600 pixels is recommended.
2. bbe provides the corresponding logo.bin file.
3. Copy logo.bin to a USB flash drive.
4. Insert the USB flash drive into the 10cells.
5. The instrument displays “Importing PDF logo from USB”.
6. Once the import is complete, the logo is automatically included in PDF reports from the next measurement onwards.

To set the date and time on the 10cells 3:

1. Open Options → Date & Time.
2. Select Set UTC Time.
3. Set the UTC date and time by using the up and down arrows for the month, day, and time.
4. The changes are applied automatically while adjusting the values; no separate confirmation is required.
5. Set Local Timezone in the Date & Time menu to the appropriate time zone for your region. This determines the displayed Local Timestamp.

Make sure that the time entered under Set UTC Time is actually UTC.

After setting the date and time, it is recommended to switch the instrument off for approximately one day and check whether it retains the correct date and time. If the date or time is lost after powering down, the internal timekeeping battery may be depleted and may need to be replaced.

The battery test is available from firmware version 1.3.0 onwards.

Under normal conditions, the 10cells should be able to perform at least 250 measurements per full battery charge. Depending on the battery condition and the individual tolerances of the electronic components, up to approximately 400 measurements may be possible with a new battery. The number of measurements that can be performed per charge will generally decrease as the battery ages. In practical operation, the actual number of measurements may be lower because the instrument is often not used continuously. Waiting times, sample preparation, and other interruptions between measurements also consume battery power.