Rtd Sensors - Newport 6000 Operation And Maintenance Manual

Chapter 5
5.4.4.2.4.2 Two Point Calibration Method
The calibration described in this section is independent of the calibration procedure
described in sections 7.3.4 and 7.3.6. Those sections deal with the internal calibration
of the TEC module, while the following calibration procedure is for calibrating the
external AD590 or LM335 sensor. For the most accurate possible results, both
calibration procedures should be performed.
The accuracy of this procedure depends on the accuracy of the externally measured
temperature. It is used to determine the zero offset of the device and the gain (slope).
5.4.4.3

RTD Sensors

The following equation is used in temperature to resistance conversions:
R
T
R
T
where: R
and enter the new C1 value.
1. Allow the 6000 to warm up for at least one hour. Select the desired
sensor type in the setup menu.
2. Set the C1 parameter to zero. Set the C2 parameter to 1.
3. Place the sensor at an accurately known and stable temperature, T
Connect the sensor to the 6000 for normal Constant temperature
operation. Allow the 6000 to stabilize at the known temperature, T
and read the displayed temperature, T
4. Repeat Step 3 for another known temperature, T
corresponding displayed temperature, T
should at the bounds of the intended operating range. For best results,
make the range between T
5. Determine the new value of C1 and C2 from the following calculations.
6. Enter the new C1 and C2 values.
= R [1 + C1 x T - C2 x T
0
= R [1 + C1 x T - C2 x T
0
is the resistance in Ω at temperature T.
T
T is the temperature in °C.
Temperature Controller Operation
and T
a1 a2
C2 = (T - T ) / (T
a1 a2
C1 = T - (T
a1
2
- C3 x (T-100) x T
2
)
. Record these values.
d1
, and the
a2
. The two known temperatures
d2
as narrow as possible.
- T ), and
d1 d2
* C2)
d1
3
) for T < 0°C
for T >= 0°C
69
.
a1
a1