| 摘要 |
<p>PURPOSE:To make it possible to detect an input current with high sensitivity, by negating uniform parallel magnetic field components applied to two magnetic cores by diffential connection and using the operation amplifier in a bridge as a voltage control switching element. CONSTITUTION:Magnetic cores 4a, 4b are inserted into the central space part of a glass tube around which exciting winding 2 is wound in reversed polarity. Now, when the output of an operation amplifier OP1 is changed over to positive saturation DC voltage, the magnetic flux density level in a united magnetic core is rapidly returned to the magnetic flux density level prescribed by input current to be measure inputted to terminals 50a, 50b. As said magnetic flux density level approaches positive max. magnetic flux density, the impedance Z2 of the exciting winding 2 is lowered and, when Z2<R10 is formed, negative saturation DC voltage is generated in the output of the operation amplifier OP1. By this mechanism, the saturation DC voltage of the operation amplifier OP1 is automatically changed over every time when the united magnetic core reaches positive and negative max. magnetic flux density and this output is integrated by an operation amplifier OP2 and the direction and intensity of the input current are displayed by an indicator 19.</p> |
