Yamato DF Series, Инструкция по эксплуатации

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46
CALIBRATION OFFSET FUNCTION
Outline of Function
In the Hi-tech IV controller, the relationship between the
temperature T detected by the sensor and the display
temperature of the operation panel D is expressed by the
equation of the line which passes the two points (T
0
, D
0
) and (T
S
,
D
S
) shown in Fig. 1.
Here, T
0
is the sensor detecting temperature when the chamber
central temperature becomes the zero adjusting temperature
(normally room temperature is adopted) D
0
at the time of no
load, T
S
is the sensor detecting temperature when the chamber
central temperature becomes the span adjustment temperature
(normally working maximum temperature is adopted) D
S
at the
time of no load in the same way.
As it is clear from the facts above, conforming of the chamber
central temperature and the display temperature is guaranteed
only when there is no load and at two points shown above. In other words, it is possible for a
temperature measured at a point in the chamber does not conform to the display temperature of the
operation panel at a voluntary temperature without load.
This is the function to move the line which passes above two points to the Y axis direction in parallel
(increase or decrease y intercept of the line). The parallel movement amount including a sign is
defined as the calibration offset. This function can conform the display temperature of the
operation panel to the measurement temperature of a voluntary point in the chamber at a voluntary
temperature.
Calibration Offset
In Fig 2, D
SV
is a display temperature of the operation panel
under the condition that the temperature in the chamber is
constant for a set temperature. It is natural to say that this
value is equal to the target set temperature. D
PV
is a measure-
ment temperature of a voluntary point in the chamber under
this condition. The difference between D
PV
and D
SV
including
the sign is defined as the calibration offset. Therefore offset is
shown as below.
In Fig. 2,
△
D
b
becomes the negative value since the target set
temperature D
SV
is larger than the actually measured temperature D
PV
.
In order to conform the display temperature to the actually measured temperature, let the controller
to recognize that the temperature in the chamber differs from the target set temperature by
△
D
b
.
NOTE: The setting tolerance of the calibration offset is
 10  C in model DF811/1011 and  16  C in
model DH811/1011. Initial offset value is set at 0  C
《Example for Reference》 When fixed value operation was started with the target setting
temperature of 100℃, and we waited for sufficient time after the temperature displayed on the
control panel had reached 100℃, then we measured temperature at one point within the chamber
using a thermometer, which was 97℃.
Then adjust the control panel so that the temperature displayed on it will be the same as the
specified, i.e., 97℃, using the calibration offset function.
The calibration offset △
D
b
is calculated with the formula 1、（”actual measured temperature”
―”displayed temperature”） as shown below:
△
D
b
：
97
℃―
100
℃＝－
3
℃
D
S
Sensor detection temperature
Display temperature
(Controlled temperature)
T
0
T
S
D
0
y=ax+b
Fig. 1
センサ検知温度
表示温度（制御対象温度）
D
SV
D
PV
T
i
T
V
平行移動
△
D
b
Fig. 2
△
D
b
＝
D
PV
－
D
SV
Equation 1
Display temp.(Controlled temp)
Sensor detection temperature
Parallel
movement