DE114303C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

CLASS 21 c.

Patented in the German Empire on June 8, 1899.

In AC systems with current transformers, the magnetization work in the latter means such a considerable expenditure of energy that thereby the annual efficiency of the plant is adversely affected in a noteworthy manner.

The need for devices has therefore often emerged which make it possible to to energize the current transformers only when they are loaded should be, in the case of no load, however, the energy required for the work of magnetization to save and thereby increase the overall usefulness of the system.

The devices proposed for this indicate the endeavor to make arrangements which should make it possible, by switching on any lamp in the previously unloaded distribution system (of any extent), to effect an immediate connection of the primary supply line and vice versa. "ersr * ™" d "ufch" ~ Äu "* sscBaiten the last lamp still burning to bring about the reopening of the primary supply line or the immediate disconnection of the relevant current transformer, etc. However, the fulfillment of such conditions has to be extraordinary sensitive and intricate devices, as is the case, for example, with the subject matter of patent 74411. Without going into its details, only the characteristic feature of such arrangements, namely the use of sensitive relays (see. Relays r and T ₁ in of the patent mentioned) sen. In view of the conditions set out above, these relays are indispensable, both when the first lamp is switched on and when the last lamp that was still on is switched off again, with relay r in one case and relay r ^{1 in} the other (see Sect. 14 of this patent).

In contrast to such arrangements, the purpose of the present invention is only when handling the low-voltage main switch, the commissioning respectively. Commissioning of the current transformer. This simplification of the task offers the possibility of a practically useful To build apparatus, the use of which is indicated by name in such systems, where only in the secondary system of the current transformer some larger consumables, e.g. B. Motors are connected that are outside of the daily Working hours do not require any power supply, the complete flow of electricity to the system so have no concerns.

In the attached schematic drawing, a circuit arrangement according to the present one is shown Invention brought to the representation, namely therein mean:

'r the primary or high voltage winding,

t the secondary winding of a transformer,

a ¹ and a ² its high and low voltage switches,

τη a temporarily switched on load,

f some kind of remote switch and

b an auxiliary power source (e.g. some drying elements).

If the current transformer is now to be loaded, the switch a ^{1 is} closed and the auxiliary power source b is thereby switched on. From the same a current goes to the lever /? through the stop d in the coil e and through the switch a ² back to b \ the electromagnet is excited and attracts the armature c . The latter rotates around the axis χ and thereby triggers the locking device η . As a result, the solenoid core k becomes free, falls, its weight interrupts the auxiliary circuit at d, and at the same time closes the high-voltage switch α ^l and thereby the primary winding r of the current transformer, which in turn feeds the load m through the secondary winding t.

If the load is to be switched off, the switch a ' ^{2 is opened} and the secondary circuit of the current transformer is thereby interrupted. At the same time the Hülfsstromschlufsstückes i with the Ausschalterhebel a ^'2, the current circuit of the coil s closed, this excites strong alternating current, the core K in the coil drawn and by touch thereby the with the core k opened mechanically connected high-voltage switch a ^1. The lever h rotates under the action of the counterweight g back to its rest position until it touches d, but without thereby closing the auxiliary circuit, since it is already interrupted by the low-voltage switch a ² . The pawl η can therefore enter the notch of the core k unhindered, whereby the latter is held in its height position and the high-voltage switch in its open position.

The electromagnetic switching device always remains de-energized in its rest position.

It goes without saying that the switch arrangement described can easily be used with the switch-on device a driving machine can be combined, with the power switch lever the starter takes the place of the low-voltage switch.

Claims (1)

Patent claim: Switching device to avoid the no-load work in temporarily unloaded current transformers when the primary switch locked in the open position is triggered and closed electromagnetically by closing the secondary switch using an auxiliary power source, characterized in that when the secondary switch (a ² ) is opened, the secondary winding is caused by the same movement (t) of the current transformer is switched to a coil (s) which influences an iron core (k) or armature in such a way that its movement opens the primary switch [a ¹ ) , whereupon the core remains held in place by a locking device (s), which is triggered when the secondary switch (d ² ) is switched on again by the auxiliary power source (b) which directly influences the electromagnet (e) . For this purpose ι sheet of drawings.