Scale/Offset Wizard: Calculate Load Cell Scale and Offset

To access the Scale/Offset wizard:
In Axis Tools, in the Axes Parameters Pane, click the Setup tab. Expand the Tools and Wizards section. Click Launch to open the Scale/Offset Wizard.

The Calculate Load Cell Scale and Offset page of the Scale/Offset wizard applies to load cell feedback axes. This page of the wizard uses the values entered by the user to calculate the scale and offset values for the axis.

To calculate the Scale and Offset, enter values into the boxes and click Next. This topic provides details for each section of the Calculate Load Cell Scale and Offset page of the wizard.

Calibration Data Method

1. Desired force units

Enter the desired force units for the axis. These will be displayed in Axis Tools.

2. From your load cell calibration sheet, enter the force values and corresponding millivolts per volt values for your load cell.

For unidirectional load cells (tension-only or compression-only load cells):

Enter the force and corresponding millivolts per volt at the rated load.

For bidirectional load cells (load cells with both tension and compression):

Enter the force and corresponding millivolts at the positive rated load and the negative rated load.

3. Zero Balance

From the datasheet, enter the millivolts per volt value at zero force. This may be called ‘zero balance’.

Enter the units of the values you entered. Notice that these units can be different than those entered in step 1. The wizard will apply the proper conversion so that the force units of the axis will be correct as displayed in the units selected in step 1.

Force/Voltage Method

1. Desired force units

Enter the desired force units for the axis. These will be displayed in Axis Tools.

2. Millvolt per Volt readings at two different force values

For unidirectional load cells (tension-only or compression-only load cells):

Physically measure two different force values, and enter the corresponding Millivolts/Volt (as shown in the Feedback section of the All tab in the Axes Status Registers Pane). The Use Current mV/V button will insert the current value of the Millivolts/Volt.

For best results, the two force values should be at zero and the maximum of the expected range, or at the high and low end of the range.

For bidirectional load cells (load cells with both tension and compression):

Physically measure three different force values, and enter the corresponding Millivolts/Volt (as shown in the Feedback section of the All tab in the Axes Status Registers Pane). The Use Current mV/V button will insert the current value of the Millivolts/Volt.

The three force values should be a large positive force, a large negative force, and a force close to zero.