Applications, Four terminal resistance measurements – Time Electronics 1030 Voltage & Current Source User Manual
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1030 Technical Manual
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5.
Applications
5.1. Four Terminal Resistance Measurements
Accurate measurements of low ohm values, such as P.R.T, can be performed by using
the 1030 as a current source and measuring the voltage across the LOAD with a DVM.
From Ohms Law : V/I=R
Resistance vs Temperature Relationship for Platinum
Resistance Thermometer Detector Element (DIN 43760)
°C
Ω
°C
Ω
°C
Ω
°C
Ω
-200
18.48
60
123.24
320
219.12
580
307.15
-180
27.08
80
130.89
340
226.17
600
313.59
-160
35.53
100
138.50
360
233.17
620
319.99
-140
43.87
120
146.06
380
240.13
640
326.35
-120
52.11
140
153.58
400
247.04
660
332.66
-100
60.25
160
161.04
420
253.90
680
338.92
-80
68.33
180
166.46
440
260.72
700
345.13
-60
76.33
200
175.84
460
267.49
720
351.30
-40
84.27
220
183.17
480
274.22
740
357.42
-20
92.16
240
190.45
500
280.90
760
363.50
0
100.00
260
197.69
520
287.53
780
369.53
20
107.79
280
204.88
540
294.11
800
375.51
40
115.54
300
212.02
560
300.65
820
381.45
Using this technique, the current passed through to the resistor can be limited to a
known value, and lead resistance does not effect the accuracy of the readings.