US1659515A - Metal-clad electric switch gear - Google Patents

Description

Feb. 14, 1928.

H. W. CLOTHIER ET AL METAL GLAD ELECTRIC SWITCH GEAR Filed April 21. 1925 2 Sheets-Sheet l 1) a gmz w T J1 Ike/771 741 Feb. 14, 1928. 1,659,515

H. w. CLOTHIER ET AL METAL GLAD ELECTRIC SWITCH GEAR Filed April 21. 1925 2 Sheets-Sheet 2 Patented Feb. 14, 1928.

UNITED STATES 1,659,515 PATENT OFFICE.

HENRY WILLIAM CLOTHIER, OF WALLSEND-ON-TYNE, AND ARCHIBALD ALLAN, 0] NORTH SHIELDS, ENGLAND, ASSIGNORS TO A. REYROLLE & COMPANY LIMITED, 0] HEIBBURN-ON-TYNE, ENGLAND, A COMPANY OF GREAT BRITAIN- METAL-CLAD ELECTRIC SWITCH GEAR.

Application filed April 21, 1925, Serial No.

This invention relates to metal-clad electric switch gear of the general type which comprises a fixed portion carrying the busbars, cable connections etc., and a removable or draw-out portion carrying the main oilbreak switch which is capable of being withdrawn after the isolating switches have been opened.

Heretofore the removable or draw-out portion has usually been arranged to move in a horizontal plane say on rails projecting at right angles from the frame supporting the fixed portion. In some constructlons however, as in those described in the specification of British Letters Patent No. 110808, 1-1. W. Clothier and A. Reyrolle & Company Limited. the draw-out portion moves in a vertical plane.

In the improved switch gear according to this invention the movement of the draw-out portion is in a vertical plane but the arrangement and disposition of the parts differ from those described in the above mentioned specification and result in a. switch gear of compact form and eflicieutand convenient arrangmcnt particularly suitable for use with a duplicate busbar system although not necessarily restricted to such an application.

A metal-clad oil-immersed switch gear according to this invention comprises an upper oil-containing chamber for a busbar isolating switch, an intermediate oil-containing chamber for a plug and socket or other draw-out connection between the busbar isolating switch and one conductor of a main oil-break switch, another intermediate oilcontaining chamber containing an isolating or selecting switch between the other main switch conductor and an out-going cable or the like, and an oil-immersed main switch in a tank beneath the intermediate chambers and removable in a substantially vertical plane.

The lowering ear for the removable portion is arrang so that either the main switch with its conductors and tank can be lowered as a whole after the isolating switches have been opened and the oil drained from the intermediate chambers, or the tank only can be lowered to give access to the main switch which remains in position.

Preferably the two intermediate oil-containing chambers are separate compartments 24,854, and in Great Britain Kay 28, 1924.

of one tank structure and are divided from each other by partitions, the space between these partitions being utilized for housing the operating gear for the main switch and as a vent chamber from the main switch tank. Alternatively a vent pipe may be provided with a telescopic arrangement to allow of the lowering of the main switch and its conductors relatively to the intermediate chambers.

As above mentioned the one intermediate chamber contains a draw-out connection of the plug and socket type or other convenient type and the other intermediate chamber contains an isolating switch serving to connect the conductor passing into the chamber from the main switch with an out-going cable or the like. Conveniently there are two such switches in this chamber one connected say to an out-going cable and the other to a duplicate out-going cable or to a potential transformer. Where there are two switches provided they are each arranged to make contact with the conductor from the main switch which may carry clip or other contacts for the ends of the switch arms. These contacts are withdrawn when the removable portion of the gear is lowered the switches having previously been opened for isolating purposes. The switch or switches in this intermediate oil-containing chamber may be arranged so that they can be moved into a definite earthing position. The switch gear is preferably arranged so that the busbar enters the. upper oil-containing chamber from the front and leaves it from the rear through suitable insulators secured by flanged oil-tight connections. By such an arrangement the length of the busbar is in the same vertical plane as the main switch and the conductors to and from it and the switch gear element or panel can therefore be fairly narrow. Instead of the busbar actually passing through the up er oil-containing chamber it may pass a ove it and a T-connection may be brought from it down through the top of the chamber through a suitable insulator. By either of these arrangements the busbar can be brought up to and away from the chamber in a pipe filled with oil. In any case the busbar or the connection therefrom is provided inside the upper oil-containing chamber with a contact for an isolating switch contained in the chamber and pivoted to the 'said conwhich registers with the draw-out connec-' tion of the oil switch. Interlocking mechanism may be provided whereby neither busbar isolating switch may be moved into the earthed position unless the other is in the ofi position.

In a preferred construction the bottom plate of the two intermediate oil-containing 'tanks or compartments forms the main supporting member for the gear and is carried on suitable legs forming a supporting framework. To it is attached by bolts or other detachable fastenings the top plate of the main switch tank, the conductors from the main switch passing up through oiltight openings in the topplate and the bottom plate of the intermediate chambers. To the underside of the top plate of the switch the tank for the switchis attached again by detachable fastenings. The lowering gear may consist of pulleys mounted on'the fixed portion and other pulleys on the tank with a wire rope or the like passing over the pulleys to a winch, If thefastenings between I the tank and the top plate are detached the tank with the oil which it contains can belowered to give access to the main switch. If on. the other hand the fastenings between the top plate of the switch and the intermediate chambers are detached the operation of the same lowering gear will cause the whole' main switch with its tank and conductors to move downwards relatively to the intermediate chambers. In this latter case the oil would first be drained out of the-intermediate chambers.

The various isolating or selecting switches mentioned are operatedeither by gear located above the oil level or by gear passing through oil-tight glands in the chambers.

Any convenient and usual interlocking arrangements may be provided so that it is impossible toefiect either of these lowering operations until the main switch and its conductors are efiectively isolated. Similarly lmown arangements are provided so that the main switch contacts must be open before the isolating switches are opened.

In the accompanlying drawings, Figure 1 is an e evat'ion, viewed from th back of one construction of metal-clad switch gear according to this invention,

Figure 2 is an end elevation partly in section and with portions removed,

Figure 3 is a plan, portions being removed in the switch gear element or panel shownat the left-hand of the figure whilst the middle and right-hand elements are sections on the lines 33 and 3*3 respectively of Figure i 2, and

Figures 4 and 5 are elevations showing alternative methods of running the busbar connections.

All the figures are diagrammatic, the details of constructidnbeing omitted.

The upper oil-containing chamber A is the busbar isolating switch .chamber and contains a switch B capable of being moved into two or three positions relative to a fixed busbar contact C, namely on and ofi or on, ofi and earthed. On and ofi positions only are shown in the drawings.

yThis switch B is connected by a conductor passing through an insulator D to a contact E in an intermediate oil-containing .chamber. F. With this contact E a brush contact G cooperates, connected to one pole of the main oil-break switch H by a conductor passing through an insulator J the parts E and. G

forming a draw-out connection. An earthing connection may be provided forthe contact E as indicated diagrammatically at E? (Figure 2) The oil tank H for the main switch is suspended by ropes K passing over pulleys K on the tank and over pulleys K on part of a fixed framework L. The tank is nor-v mally held up against the top plate M to which it is attached by bolts or like detachable fastenings (not shown). This top plate M is itself connected by bolts or the like to 1 the bottom of the intermediate oil-contain; ing chamber F.- As may be seen from Figures 1 and 3 the three tanks of a three-phase unifi switch gear are suspended by two single ropes K one on each side, each rope being attached to a drum on a spindle which can be rotated by worm gear N and by undoing the appropriatebolts or other fastenmgs between any tank and its top plate M or between any top plate M and the bot-- tom of the chamber F, either the tank H' may be lowered (see the middle portion of Figure 1) leaving the main switch in position, or thetank H, its top plate M and the main switch may all be lowered relatively to the fixed framework.

The other pole of the main switch is connected by a conductor passing through an nsulator-J to a brush contact J cooperatin with a fixed contact 0 mounted on an insu ato r 0', contained in another intermediate oil-containing chamber F which may convemently form part of the same structure as the chamber F. As shown in Figure 2 the two chambers F and F are separated by a space F which accommodates the operating mechanism H for the rod H of the main switch. The space F is shown as provided with a vent pipe F leading to any suitable outlet and holes F are provided for the passage of gases from the oil switch tank into the space F.

In the chamber F are two switches P and P (Figure 3) each pivoted in clips carried by a rod 0 (Figure 2) in electrical connection with the contact 0 and supported by the insulator 0'. One of these switches P when closed, makes connection with a clip P at the end of a conductor leading through an insulator P say to an out-going cable and the other switch P to a similar clip P on a conductor leading through an insulator P to, for instance, a duplicate out-going cable or to a potential transformer. These switches P and P act as isolating switches and may be provided with earthing contacts which, however, are not shown in the draw- I ings. Alternatively earthing switch arms may be provided as at P whereby either out-going connection may be earthed.

The switch gear illustrated isintended for use on a duplicate busbar system and therefore two busbar isolating switch chambers A are shown in Figure 1 each with its switch B. The conductors and insulators D are duplicated in the intermediate oil-containing chamber F where the conductors are joined by a bar E (Figure 2) carrying the contact E with which the brush contact G cooperates. Thus either one or both busbars may be placed in commission by suitable manipulation of the switches B.

Oil-tight joints are provided between the various tanks and when it is desired to lower the whole of one of the main switches with its tank and top frame, the oil in the intermediate chambers F and F is first withdrawn.

It will be seen that by means of the earthng arrangements previously mentioned, the improved switch gear can be rendered quite safe for handling when the main oil switch is removed, for all the contacts to which access is then possible may be placed at earth potential and any other parts remaining at higher potentia1as for instance the busbarsremain within their metal-clad oilfilled chambers.

The busbars may be led into the chambers n any suitable manner but the arrangement 1S preferably such that the busbar lies in sustantially the same vertical plane as its main switch and the conductors to and from it. The busbars may be in oil-filled pipes R and in Figures 2 and 4 these pipes R make oil-tight joints with openings in the front and back walls of the busbar chambers A of the switch gear. In Figure 5 the line of the busbar pipe R, although in the same vertical plane as in Figures 2 and 4, passesover the busbar isolating switch chamber A and a T-connection is made through an insulator R in the top of the chamber from the busbar to the contact C.

It will be understood that any suitable operating mechanism, such for exam 1e as is shown diagrammatically at S and (Figure 2) may be provided for the various switches but the present invention is not concerned with the details of such mechanism .nor with interlocking gear to prevent for instance the isolating switches being opened before the main switch is opened or the tank being lowered before the isolating switches are opened. Interlocking gear having generally similar functions is known in present day practice in oil-immersed switch gear.

What we claim as our invention and desire to secure by Letters Patent is 1. In metal-clad oil-immersed electric switch gear, the combination of an upper oilcontaining chamber, a busbar connection within said chamber, an intermediate oilcontaining chamber, an insulated conductor leading from the upper chamber to the intermediate chamber, a switch in the upper chamber serving to connect said conductor and the busbar connection, a second intermediate oil-containing chamber, a contact within such chamber, an out-going conductor in such chamber, a switch serving to connect said contact with said out-going conductor, a tank beneath the intermediate chambers, an oil-immersed main switch in said tank, draw-out connections between the poles of said main switch and the conductor in the first intermediate chamber and the contact in the second intermediate cham ber respectively, means for lowering the tank and the main switch, and means for lowering the tank independently of said main switch.

2. 1n metal-clad oil-immersed electric switch gear, the combination of an upper oil-containing chamber, a busbar connection within said chamber, an intermediate oilcontaining chamber, an insulated conductor leadin from the upper chamberto the intermediate chamber, means within the intermediate chamber for connecting said insulated conductor to earth, a switch in the upper chamber serving to connect said conductor and the busbar connection, a second intermediate oil-containing chamber, a contact within such chamber, an out-going conductor in such chamber, a switch serving to connect said contact with said out-going conductor, means within the sceond intermediate chamber for connecting the out-going conductor to earth, a tank beneath the intermediate chambers, an oil-immersed main switch in said tank, draw-out connections between the poles of said main switch and the conductor in the first intermediate chamber and the contact in the second intermediate chamber respectively, means for lowering the tank and the main switch, and means intermediate oil-containing chamber, an insulated conductor leading from each of said upper chambers to said intermediate chamber, a connection in the intermediate cham ber between said conductors, a contact on said connection, a switch in each upper chamber serving to connect the busbar coniiectionavitll the insulated conductor, a second intermediate oil-containing chamber, a contact within such;chamber, an out-going conductor in such chamber, a switch serving to connect said contact with said out-going conductor, a tank beneath the intermediate chambers, an oil-immersed main switch in said tank, draw-out connections between the poles of said main switch and the conductor in the first intermediate chamber and the contact in the second intermediate chamber respectively, means for lowering the tank and the main switch, and means for lowering the tank independently of said main switch.

4. In metal-clad oil-immersed electric switch gear, the combination of a plurality of upper oil-containing chambers, a busbar connection within each of said chambers, an intermediate oil-containing chamber, an insulated conductor leading from each of said upper chambers to said intermediate chamber, a connection in the intermediate chamber be- I tween said conductors, a contact on said connection, a switch in each upper chamber serving to connect the busbar connection with the insulated conductor, means within the intermediate chamber for connecting said insulated conductor to earth, a second intermediate oil-containing chamber, a contact within suchchamber, an out-going conductor in such chamber, a switch serving to connect said contact with said out-going conductor,.

means within the second intermediate chamber for connecting the out-going conductor to earth, a tank beneath the intermediate chambers, an oil-immersed main switch in said tank, draw-out connections between the poles of said main switch and the conductor in the first intermediate chamber and the contact in the second intermediate chamber respectively, means for lowering the tank and the main switch, and means for lowering the tank independently of said mam switch.

15. In metal-clad oil-immersed electric switch gear, the combination of a plurality of upperoil-containing chambers, a busbar connection within each of said chambers, an intermediate oil-containing chamber, an insulated conductor leading from each of said upper chambers to said intermediatecham her, a connection in the intermediate chamber between said conductors, a contact on said connection, a switch in each upper chamber serving to connect the busbar connection with the insulated conductor, means within the intermediate chamber for connecting said insulated conductor to earth, a second intermediate oil-containing chamber,

a contact within such chamber, a plurality of out-going conductors in such chamber, a plu- 6. Metal-clad oil-immersed electric switch gear havin the .combination of parts claimed in c aim 1 in which the main switch is supported on a cover separable from its.

tank, the cover and the tank being provided with pulleys round which a rope passes, such rope passing also round pulleys on a fixed frame-work substantially as set forth.

7 Metal-clad oil-immersed electric switch gear having the combination of parts claimed in claim 1 in which the busbar having a connection within the upper oil-containing chamber lies in substantially the same vertical plane as the main switch and the conductors to and from such switch.

In testimony whereof we have signed our names to this specification.

HENRY WILLIAM cLo'rnmR." ARCHIBALD ALLAN. A

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