ST2515 Operation Manual
20
10°C, after correction, the value will be displayed as 96.22Ω.
Temperature conversion function: For the existence of temperature heating effect, the value of
resistance varies with temperature. In this case, the temperature of the resistor will be higher
than that of the environment. ∆t is the temperature difference.
Pt
(1)
Temperature correction (TC): By this function, the resistance tested under the current
environment temperature will be converted to a resistance value under the user-set
environment temperature. For instance, a resistor is tested as 100Ω under 20°C. If user sets
the temperature as 10°C, after correction, the value will be displayed as 96.22Ω. This is
realized by formulary conversion.
Formula: R
t
=R
t0
*{1+ α
t0
*(t-t0)}
R
t
Resistance measured under the current environment temperature
R
t0
Resistance after correction
t0
Preset temperature
t
Current environment temperature
α
t0
Temperature coefficient of the material
For example: A resistor is measured as 100Ω under 20°C (Suppose the temperature coefficient as
3930ppm), the resistance under 10°C will be 96.22Ω.
=96.22Ω
NOTE:
1.
The probe temperature of the temperature sensor is the environment temperature yet not
the surface temperature of the probe.
2.
Before measurement, it is necessary to warm up the instrument and the probe for about
half an hour. The temperature sensor should be placed to the DUT as close as possible but
cannot contact it. After the displayed result comes to be stable, you can read or record the
result.
(2)
Temperature conversion (∆t): Basically, resistors have heat effect. Temperature conversion
represents the temperature difference between the resistor and the environment.
∆t=R2/R1 (k+t1)-(k+ta)
∆t is the temperature increment.
t1 is the temperature at the start of resistance measurement.
