Chino KP 2000 Series, Instructions Manual

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Ideal value line is a straight line when there is no measurement error. If 'input value equivalent to 0
℃
' is
entered, 0 ℃ is indicated whereas when 'input value equivalent to 1000 ℃ ' is entered, 1000 ℃ is indicated.
Thus according to the expression as there is no correction value, Y=X.
In case of sample value line, as compared to ideal value line, it shifts to + side by b units in the neighborhood
of 0 ℃ and the tilt of straight line lowers.
For example when 'input value equivalent to 0
℃
' is entered' +20
℃
is indicated and when 'input value
equivalent to 1000 ℃ ' is entered, 1005 ℃ is indicated and so on.
Thus bias(b) equivalent to -20
℃
is added and multiplication by a coefficient that increases the tilting is done
and thus ideal straight line is obtained. In other words, indicator shift can be lost.
Thus the expression is Y=aX-b.
10-14-3. Input related scale correction
Details about the procedure for input related (measurement range, CT input) scale correction are as follows.
Scale correction of measurement range is done in the measurement range that is selected, hence if other
measurement scale is scale is selected after correction, indicator shifting occurs. This is because even when
any measurement range is selected, the scale correction function operates with the same scale correction value.
After the scale correction if measurement range is changed, perform scale correction again.
1. Preparations related to measurement device
Input to be corrected Required measurement device and instruments
Measurement range
①
High precision voltage current occurrence device
Ú
Required for
thermocouple, DC
voltage, DC current
correction.
･ Accuracy: Less than ±0.05%.
②
Digital multi-meter
Ú
Required for
thermocouple, DC
voltage, DC current
correction.
･
Accuracy: Less than ±0.05%.
･ If the accuracy of the voltage current occurrence device of clause ① is not
good, confirm the voltage value (current value) using digital multi-meter also.
③
Dial resistance
Ú
Required in correction
of resistance
thermometer.
･
Accuracy: Less than ±0.05%.
④ Thermocouple
Ú
Required in correction
of thermocouple.
･
JIS:0.4 level.
⑤ Freezing point expression reference junction
Ú
Required in correction
of thermocouple.
･
Accuracy: Less than ±0.1
℃
.
･ Freezing point device that uses triple point of water.
CT input
(Heater snapping
wire alarm)
①
AC current occurrence device
･ Accuracy: Less than ±0.2%.
Warning
To avoid serious accidents always cut off the power supply and then do
the wiring.