Beckhoff ELX3351, Руководство по эксплуатации

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Parameterization and programming
ELX3351 41 Version: 1.3.1
• Self-calibration: continuously repeated self-calibration of the terminal for the improvement of the
measuring accuracy
• Tare: repeated gross/net compensation by taring
5.3.1 Sensor calibration
The ELX3351 is matched to the characteristic curve of the sensor element by means of the calibration. Two
values are required for this procedure: the initial value without a load (zero balance) and fully loaded (rated
output). These values can be determined by a calibration protocol or by a calibration using calibration
weights.
Fig. 33: Adaptation to the sensor curve
Calibration by means of compensation in the system
In the practical calibration, measurement takes place first with the scales unloaded, then with a defined load
on the scales. The ELX3351 automatically calculates the existing sensor characteristic values from the
measured values.
Sequence:
1. Perform a CoE reset with object 0x1011:01
see Restoring the delivery state
2. Activate mode 0 via the control word
3. Set scale factor to 1 ( 0x8000:27 [
}
60] )
4. Set gravity of earth ( 0x8000:26) [
}
60] if necessary (default: 9.806650)
5. Ste gain to ( 0x8000:21 [ } 60] ) = 1
6. Set tare to 0 ( 0x8000:22 [
}
60] )
7. Set the filter ( 0x8000:11 [
}
60] ) to the strongest level: IIR8
8. Specify the nominal load of the sensor in 0x8000:24 [
}
60] ("Nominal load")
9. Zero balance: Do not load the scales
As soon as the measured value indicates a constant value for at least 10 seconds, execute the com-
mand 0x0101 (257
dec
) on CoE object 0xFB00:01.
This command causes the current mV/V value( 0x9000:11 [
}
62] ) to be entered in the "Zero balance"
object.
Check: CoE objects FB00:02 and FB00:03 must contain "0" after execution