How to calibrate

Double click the loadcell module in the Card Properties of Project windows.

 

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Then Status window will be activated below.

 

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In case of calibrating channel 1
Set the weight to zero when the module is wired with loadcell unit.
If you press the "Calib." Button then "Set Value"± window will be activated.

 

 

Press the "OK" button when the converted value is stable.

Then following dialog box will appear.

 

 

Press the "OK" button.

Then configuration dialog box of span weight will be appeared below.

 

 

Set the span weight and press the "OK" button when the measuring value is stable.

How to set the span weight

To set the proper span weight in the above dialog box, two kind of resolutions should be considered together.
One of them is the resolution of the loadcell itself.
Assume the specification of the loadcell is 100Kg, 2mV/V ±¾0.1% for further discussion.
As written in the above example specification, the resolution of loadcell is 0.1%, such that the actual resolution of the loadcell can be calculated from the percentage.

100g (100Kg * 0.1%)

The other resolution to be considered is WGnnA module. This module provides 1/6000(±¾0.016%) resolution, when the signal is 2mV/V. This value imply the actual weight resolution as

16g (100Kg * 0.016%)

You can understand the final and effective resolution of this example is 100g. This means high resolution(16g) of the module(WGnnA) cannot be utilized, since the signal from the loadcell sensor has 100g resolution.
Put this final resolution in your mind, and then choose the weight to load for span calibration. The loading weight should be at least 20% of maximum capacity of the loadcell.
If you choose 20Kg for span calibration, set the "°Weight"± field of the above dialog box as 200. The "°200"± is the induced value of 20Kg from your system resolution(100g) as calculated before.

 

 

Then you can see the "Calib. Completed" dialog box. This is the end of calibration of channel 1.
After the calibration, you can get this measured value using "DFRO" instruction or batch control.

All 4 channels (or 2 channels) are configured with same way.