!!"! # $!! % & ’ ( "!# ) % *" + ’# ,-( !. /01$ - 234 ! 4 * -234 - R Pt 100 = R Pt + R 2 + R 3 R Pt R 3 R 2 L 3 L 2 R Pt R 1 R 2 R 3 Ω 1 = R 2 + R Pt + R 3 Ω 2 = R 1 + R 2 L 3 L 2 L 1 R Pt 100 = R Pt + R 3 - R 1 Ω 1 - Ω 2 = R 4 R Pt R 1 R 2 R 3 DVM Constant current source R Pt 100 = R Pt L 4 L 3 L 2 L 1 I U
