| 摘要 |
PURPOSE:To obtain a measuring instrument which is manufactured and installed economically by performing temperature measuring operation at plural places which are equal in the length of external wiring by two-wire type resistance bulbs and one DC power source. CONSTITUTION:A series circuit 10 is constituted by connecting one comparison part B and plural two-wire type temperature measurement parts A1-An where the external wiring is connected to both-terminal sides of two-wire type resistance bulbs S1-Sn in series. A constant current generating means 11 flows a constant current to the series circuit 10. A voltage measuring means 15 measures respective voltages based upon fed constant currents of the comparison part B and temperature measurement parts A1-An. Then an arithmetic means 16 performs specific arithmetic as to the voltage measurement result of the voltage measuring means 15 to measure temperatures detected by the resistance bulbs S1-Sn according to the result. Then the temperature measurement parts A1-An have temperature measuring resistance elements R1-Rn which are equal in reference resistance value and external wiring coils R11, R12-Rn1, and Rn2 which are equal in resistance value, and the comparison part B is constituted by connecting two series-connected external wiring coils Rc1 and Rc2 and a 1st resistor Rc which has a resistance value equal to a reference resistance value and no temperature dependency.
|
