Beckhoff ELX3312, Руководство по эксплуатации

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Parameterization and programming
ELX3312 and ELX3314 59 Version: 1.3.0
5.3.5 Limit 1 and Limit 2
Limit 1 and limit 2, index 0x80n0:13, index 0x80n0:14
A temperature range can be set that is limited by the values in the indices 0x80n0:13 [
}
74] and 0x80n0:14
[
}
74] . If the limit values are overshot, the bits in indices 0x60n0:03 and 0x60n0:05 are set.
The temperature value is entered with a resolution of 0.1°C.
Example
Limit 1= 30°C
Value index
0x80n0:13 [
}
74] = 300
5.3.6 Calibration
Vendor calibration, index 0x80n0:0B
The vendor calibration is enabled via index 0x80n0:0B [
}
74] . Parameterization takes place via the indices:
• 0x80nF:01 [ } 75] : Vendor offset calibration thermocouple
• 0x80nF:02 [
}
75] : Vendor gain calibration thermocouple
• 0x80nF:03 [
}
75] : Vendor CJ offset calibration
Vendor and user calibration
User calibration (index 0x80n0:0A [ } 74] ) should only be performed instead of the vendor calibra-
tion (index 0x80n0:0B [ } 74] ), but this is generally only necessary in exceptional cases.
User scaling, index 0x80n0:01
The user scaling is enabled via index 0x80n0:01 [
}
74] . Parameterization takes place via the indices
• 0x80n0:11 [
}
74] : User scaling offset
The offset describes a vertical shift of the characteristic curve by a linear amount.
At a resolution of 0.1°, 1 digit
(dec)
corresponds to an increase in measured value by 0.1°
At a resolution of 0.01°, 1 digit
(dec)
corresponds to an increase in measured value by 0.01
• 0x80n0:12 [
}
74] : User scaling gain
The default value of 65536
(dec)
corresponds to gain = 1.
The new gain value for 2-point user calibration after offset calibration is determined as follows:
Gain_new = reference temperature / measured value x 65536
(dec)
User calibration, index 0x80n0:0A
User calibration is enabled via index 0x80n0:0A [
}
74] . Parameterization takes place via the indices
• 0x80n0:17 [ } 74] : User offset calibration thermocouple
• 0x80n0:18 [
}
74] : User gain calibration thermocouple
Calculation of process data
Calibration
The concept calibration , which has historical roots at Beckhoff, is used here even if it has nothing to
do with the deviation statements of a calibration certificate. Actually, this is a description of the ven-
dor or customer calibration data/adjustment data used by the device during operation in order to
maintain the assured measuring accuracy.