Patent GB-428621-A (GB)
Title: Improvements in combined electric control switch installations and miniature switchboard diagrams
IPC: B65D51/04
Filed: 1933-11-17
Abstract: 428,621. Switchboards; indicators for switches. SIEMENS-SCHUCKERTWERKE AKT.-GES., Siemensstadt, Berlin. Nov. 17, 1933, Nos. 32096 and 32097. Convention dates, Nov. 19, 1932 and Dec. 21, 1932. [Class 38 (v)] [See also Group XXXVIII] In a combined control switch installation and miniature switchboard diagram of a multiple bus-bar installation with power and disconnecting switches, the arrangement is such that it is necessary to operate only a single handle with control contacts, which is located in the line of the diagram and arranged to control and effect the opening and closing of the switches in a selected current path, in order to release all the switching processes necessary for the complete establishment or interruption of the said current path. Fig. 1 shows a diagrammatic reproduction of the system of Fig. 2 which comprises branches 8, 8<a> adapted to be connected to duplicate bus-bars 1, 2 through disconnecting-switches 3, 4 having the combined operating and indicating members 10, 20. The power switch 5 and isolating switch 6 of each branch 8 are so arranged that if 10 is operated to connect bus-bar 1 to branch 8, the disconnecting switch 3 closes first and if desired simultaneously with the closure of the switch 6 and then switch 5 is automatically closed. The reverse process takes place when 10 is opened. To change over on load, 10 is operated to open 3, 5 and then 20 is operated to close 4, 5. The positions of the various switches are indicated by the position of the bar along the line when closed or athwart when open, or where the switches 10, 20 have an intermediate position it may be oblique when the disconnecting switch only is closed. Indicating tell-tale lamps may be illuminated by pressing on the bars of the members 10, 20. When a branch 8 is to be changed over under load, or is to be connected to both bus-bars, the member 30 is operated to close two disconnecting switches 13, 14 and a power switch 15. Members 10, 20, 30 are suitably interlocked. Known arrangements may be employed for the sequential operation of disconnecting and power switches by the control switches, or relays may be employed for this purpose. In a modification, Figs. 3, 4, (not shown), only two switches 10, 20 are provided on a control panel and these are adapted to have their controlling circuits connected to the appropriate feeder switches by means of further switches, or by a selector dial which is rotated to a position depending on which feeder is to be connected or disconnected. Tell-tale lamps are provided on the diagram to show whether the correct feeder has been connected by the selector. Where a dial is employed, the first dialling may be arranged to select the feeder, and a second dialling may be arranged to perform the control action, that is, to close or open the appropriate power and disconnecting switches. Fig. 5 shows a form in which a combined selector and indicator 80 selects the current path, which is indicated by the appropriate sign 30 or 40, and then a control switch 70 is operated to the closed position shown by bar 71 to close the disconnect and then the power switch. This switch may, however, have two interlocked operating members for performing these operations in correct sequence. Earthing and isolating press-buttons 91, 92 with an indicator 90 are provided and may be blocked in dependence on the position of the power switch as shown by bar 60.