Escort 3004B User Manual
17
Appendix
Page 7
17.3.
Accuracy of the PT100 measurements
The measurement inaccuracies thereafter are given as maximum values: typical values are 2 to 3
times less.
times less.
The measurement accuracy in temperature is the sum of several possible sources of inaccuracy:
Pl: accuracy of standardisation
Pz: zero accuracy
Pm: accuracy of the measurement of the equivalent voltage
Pd: accuracy of the measurement offsets
Pz: zero accuracy
Pm: accuracy of the measurement of the equivalent voltage
Pd: accuracy of the measurement offsets
The total accuracy is then: Pt = Pl + Pz + Pm + Pd
For the recorder:
Pl =
0.25 C for the PT100
Pz =
0.25 C for the PT100
Pd =
0.10 % of the offset
Pm = given in the tables
Measurement accuracy: Pm
The measurement accuracy Pm depends on the voltage range used by the appliance. The
measurement error in degrees will then be the measurement error in voltage divided by the slope in
V/ C.
For all the voltage ranges, the accuracy is +/-0.1% +/- 10 V.
The measurement accuracy Pm depends on the voltage range used by the appliance. The
measurement error in degrees will then be the measurement error in voltage divided by the slope in
V/ C.
For all the voltage ranges, the accuracy is +/-0.1% +/- 10 V.
Slope dependiing of temperature :
Temperature ( C)
-200
-100
0
200
400
600
800
Slope ( V/ C)
378
354
342
321
301
281
260
Equivalent voltage measurement accuracy at 0 C :
Range
Temperature
Tension
Max error
( V)
Max Error
( C)
20
10
20
0.06
50
20
30
0.09
100
50
60
0.18
200
100
110
0.32
500
200
210
0.60
1000
500
510
1.50
2000
1000
1010
3.00
Range
EXAMPLE OF ACCURACY CALCULATION
The measurement is about 240 C made with the 500 C range, centered on 0 C (non zero offset)
with a PT100 probe.
with a PT100 probe.
Pt = Pl + Pz + Pm + Pd