Chroma 16502 - Temperature Correction Function

Descriptions of Temperature Measurement and Correction Function
8-7
8.3 Description for Temp. Correction Function
Temp. correction function is mainly by using the resistance value of known specific
temperature(for instance, 30°C is 100Ω) of lead(ex. copper, aluminum wire) as well as known
temp. coefficient (ex. 3930PPM) to infer the other resistance value when temp. is 20°C.
1. Temp. correction formula
Rt0 = Rt/{ 1+
αt0* (t-t0) }
Within:
Rt0: Specified temp. resistance value that you want to convert
Rt: The measured resistance value under ambient temp.
t0: Coefficient of specified temp.
t(°C): Ambient temp.
t0 (°C): Specified temp. that you want to convert
2. Example:
In this example, the ambient temp. is 30°C, meanwhile the resistance value of measured
copper wire is 100Ω. How many the resistance value is when you want to convert
20°C? The user needs to input the value (20°C) which want to convert and temp.
coefficient. When the conduction coefficient closes to 1, thus temp. coefficient of
copper is 3930 ppm.
The condition of calculation is 100Ω copper wire under 30°C ambient temp.. The
conversion step of resistance value under 20°C ambient temp., please follows 3930 ppm
temp. coefficient.
Rt0: Unknown resistance value
Rt: 100Ω
t0: 3930 ppm
t(°C): 30 °C
t0 (°C): 20°C
Rt0 = Rt/{1+
αt0 * (t-t0)} = 100 / {1 + (3930 e-6) * (30 - 20)} =96.21 Ω
8.3.1 Setting Description
The setting of temp. correction is mainly converting two conditions of specified temp. t0 (°C) of
resistance along with lead temp. coefficient t0 for accomplishment of resistance value under
specified temperature.
Setting steps:
1. After powered-on, press [System Setup] to enter the screen as follows.
S Y S T E M S E T U P >
C A L B R A T I O N
M
E M
M
A N
A
G E
S Y S T E M C O N F I G
F2
F3
← Set the System Parameter
F4
F1