| 摘要 |
395,347. Switching systems; distantcontrol systems. AKTIESELSKAPET ELEKTRISK BUREAU, 17, Middelthunsgate, and AANDERUD, A., 32, Sorgenfrigaten, both in Oslo, Norway. Oct. 2, 1931, No. 27461. [Class 38 (iv).] In a system for the remote supervision of a plurality of substations connected to a main station over common line wires, the conditions of apparatus at the substations may be ascertained by connecting the stations to the line wires in succession so as to facilitate the transmission of supervisory signals having frequency characteristics which are indicative of the conditions of the apparatus at the various stations. The substations are employed for switching on or off power circuits and the system is such that switching is effected simultaneously at all substations by control current transmitted from the main station. A plurality of line circuits may radiate from the main stations, each line circuit being associated with a plurality of substations. Figs. 1, 2 and 3 show the substation equipment and Fig. 4 the equipment at the main station. Each substation has three line relays P, Q, RR connected in series with the line wires a, b which are connected at the main station to a control key N<1> and through a transformer CTT to a supervisory key N<2> impulse transmitting equipment and telephone apparatus. Normally the line circuit is closed over the contacts of the key N<1> in the position shown and relays Q at all substations together with relay CA at the main station are energized. Each pair of lines is provided with a jack LJ at the main station so that the main station may be selectively connected to a particular line or different lines may be inter-connected through cord circuits. Control of substation apparatus. As shown the position of the key N<1> corresponds to the " open " positions of the substation switches Sw. To close the substation switches, the key N<1> is operated so that the contacts b are moved to the right and reverse the polarity of the line current. The station relays P are then operated to energize relays A and in consequence the locking relays K which operate relays N to switch on the motors M<0> and thereby close the power switches at the substations. Upon operation of each motor a corresponding change-over-switch is operated and a contact m<1> reversed so as to prepare the " opening " circuit for the associated power switch. To open the power switches, the key N<1> is restored to reverse the line circuit and cause operation of relays Q, B, L, O which again operate the motors to open the switches. A lamp CCC controlled over the contacts of key N<1> indicates the condition of the substation power switches. During operation of the motors earth is applied to the b line over contacts k<3> or 13 to shortcircuit relay CA in the main station and operate a supervisory lamp CAA. |
