| 摘要 |
<p>PURPOSE:To obtain a transformer for earthed measuring instruments which is capable of securely lowering secondary voltage on the lack of phase due to primary side fuse blow for example and whose heat generation loss is very small during normal operation. CONSTITUTION:The heat generation loss during normal operation is decreased very small by using in place of resistors the reactors with the corresponding value obtained through numerical analysis to secondary and tertiary loads. The reactance values of two sets of secondary additional reactors 15 and 17 are obtained through numerical analysis so that the voltage between secondary lines and the 0-phase voltage that are required on primary phase lack may be obtained to correspond to the reactance values of the small power-factor low-voltage relays 13 which serve as secondary and tertiary loads, and the operation of either or the both of two low- voltage relays and that of an earthed overvoltage relay are secured. If said secondary additional reactor 15 has already been specified, numerical analysis is made, and an additional reactor 17 or an additional condenser 18 is inserted in a tertiary circuit.</p> |
