Salter Brecknell 308BP - Manual (Page 19)

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CHAPTER 6: SCALE CALIBRATION
6.1 SCALE CALIBRATION OVERVIEW
The 308-BP scale may be calibrated with any precision test weight from 10% to 100% of full-scale
capacity. The test weight unit must be in grams. The recommended test weight is about 2/3 of the
full-scale capacity, but in general, the larger the test weight, the more accurate the scale will be.
The scale allows for three-point calibration. The three calibration points are denoted C1-C3. You
may use C1 only if you like. If you do use all three calibration points, they must be in ascending
order, e.g. C1 = 2 kg, C2 = 5 kg and C3 = 10 kg.
The scale calibration also features an optional Adjust Calibration mode. This mode allows you to
“tweak” the span calibration after it has been completed. See Section 6.3 for more information.
6.2 SCALE CALIBRATION PROCEDURE
1. Turn the scale off. While pressing and holding down the ZERO key, turn the scale back ON.
2. When the scale shows “- - - - - -“, you may release the ZERO key.
3. The message "C 0" appears on the display briefly, followed by a value that remains on the
screen. Allow a 20-minute warm-up period for the load cell and indicator to become thermally
stable.
4. Press ZERO to zero the value. The scale shows “Zero” for a few seconds to indicate that it has
acknowledged the key press.
5. Press the UNITS key to save the zero point value. The scale shows “Save” for a few seconds to
indicate that it has acknowledged the key press, followed by “Set”.
6. The display will momentarily prompt "C 1" for the span calibration, followed by "0.0”, “0.00” or
“0.000” depending on the scale capacity. The rightmost digit should be flashing
7. Use the four directional keys shown in Figure 6-1 to adjust the displayed value to the actual test
weight value. Increase the flashing digit by pressing the PRINT key. Decrease the flashing digit
by pressing the MR key. The position of the flashing digit may be changed by pressing the ZERO
key or the SAMPLE key.
Figure 6-1: Calibration Mode Key Assignments
8. After setting the exact value, place the test weight on the platform and press the UNITS key to
save the value. The scale shows “Save” for a few seconds to indicate that it has acknowledged
the key press.