| 摘要 |
<p>PURPOSE:To remarkably enhance workability, by using a short bar as a non- linear resistor element to enable calibration under such a state that said resistor element is connected to a check terminal. CONSTITUTION:Non-linear resistor elements D1, D2 are provided to check terminals 3, 3a in such a manner that two diodes are used as rectifiers and connected in parallel in mutually reversed polarity relationship. When the voltage between the check terminals is positive, the diode D1 is brought to a short circuit state in a regular direction at the time of non-calibration to accomplish the function of a short bar and the diode D2 is brought to an open state in a reverse direction. At the time of calibration, the diode D1 is in the regular direction but, because shows high resistance as compared with the internal resistance of a measuring device M, becomes similar to a short bar detached state and all of a current is flowed to the measuring device M. The state at the time of non- calibration is automatically restored if the measuring device is detached after calibration and the diode is again made equal to one having the short bar connected thereto.</p> |
