
Appendix 12 JEC 2137 Induction Machine-compliant Resistance Measurement
A28
Standard JEC 2137 specifies the determination of resistance values according to the fol-
lowing formula:
Transforming Formula 1 provides the following:
............. Formula 2
On the other hand, Formula 3 shows the temperature correction process with the RM3545.
So the temperature coefficient to be set is determined as shown in Formula 4.
................................ Formula 3
.................................................... Formula 4
For example, if the reference temperature is 20°C, set the temperature coefficient for the
instrument as follows.
Appendix 12 JEC 2137 Induction Machine-com-
pliant Resistance Measurement
R
t
R
= R
t
T
×
t
T
+ k
t
R
+ k
......................................... Formula 1
R
t R
Winding resistance at reference temperature
t
R
R
t T
Measured value of winding resistance at
t
T
t
R
Reference temperature [°C]
t
T
Temperature of winding during measurement [
°
C]
k
Constant (235 for copper wire)
R
t
T
R
t
R
=
t
T
+ k
t
R
+ k
=
1
(
t
T
−
t
R
)
1
t
R
+ k
1+
R
t
R
=
1 +
α
t
R
× (
t
T
−
t
R
)
R
t
T
α
t
R
=
t
R
+ k
1
α
t
R
=
t
R
+ k
1
=
20 + 235
1
= 3922 [ppm/°C]
Содержание RM3545
Страница 2: ......
Страница 4: ......
Страница 26: ...Operating Precautions 18...
Страница 42: ...1 5 Checking the Measurement Target 34...
Страница 54: ...2 6 Pre Operation Inspection 46...
Страница 70: ...3 5 Checking Measured Values 62...
Страница 226: ...10 6 Supplied Connector Assembly 218...
Страница 290: ...Chapter 13 Specifications 282...
Страница 312: ...14 4 Disposing of the Instrument 304...
Страница 349: ...Appendix 18 Outline Drawing A37 Appendix Appendix 18 Outline Drawing...
Страница 362: ...Index Index 4...
Страница 363: ......
Страница 364: ......