DeltaOHM HD31, Руководство по эксплуатации

Страница: 91 / 154

HD31
- 91 -
V1.6
calibration or, failing this, the factory values.
• STANDARD PT100 : sets the user-calibration with the nominal values of the Pt100 sen-
sor. An option to be used if the probe is not calibrated and it is not possible to perform a
new calibration.
• FACTORY : sets the user-calibration equal to the factory calibration. It is useful if incor-
rect user-calibration data were entered and if you are temporarily unable to perform a
new calibration.
• PARAMETERS : displays and/or changes the coefficients of the Callendar Van Dusen eq-
uation used by the instrument to obtain the temperature depending on the resistance of
the PRT sensor (see appendix for details).
Fig. 13.1.1: PRT probe calibration types
Select the desired type of calibration using
S
and
T
, then press the F3 key ( OK command) to
confirm.
If a message is displayed reminding that the operation will change the probe calibration data,
select YES ( F3 key) to continue (or Press F1 to select NO and exit).
13.1.1 NEW TUNING
OPTION FOR
PRT
SENSORS
1. The instrument suggests that the first calibration point is set to 0 °C ( SETPOINT line). If you
don’t want the point to be calibrated, press F1 ( SKIP command) to move to the next point,
otherwise place the probe in a bath at 0 °C. The display shows the temperature value
measured by the probe ( MEASURE line). When the reading is stable, press F3 ( OK com-
mand) to confirm: the instrument displays a countdown ( ACQUIRING ) of a few seconds,
then moves to the next calibration point.
Fig. 13.1.2: PRT calibration at 0 °C
2. The instrument suggests that the second calibration point is set to 100 °C ( SETPOINT line).
If you don’t want the point to be calibrated, press F1 ( SKIP command) to move to the next
point, otherwise place the probe in a bath ranging from 95 °C to 105 °C. The display shows
the temperature value measured by the probe ( MEASURE line). The calibration point can be
adjusted using
S
and
T
. When the reading is stable, press F3 ( OK command) to confirm:
Reference value
Measured value