US2063349A - Supervisory apparatus - Google Patents

Description

L A. SHARP 2,063,349

Dec. 8, 1936.

SUPERVISORY APPARATUS Original Filed July 7, 1954 I 'VIIIIIIIIM DISTRIBUTION CONSUMPTION A TTORNEYS.

Patented Dec. 8, 1936 PATENT OFFICE SUPERVISORY APPARATUS L Alan Sharp, Bellevue, Pa., assignor to Wm. L. Grimes, Winston-Salem, N. 0.

Application July 7, 1934, Serial No. 734,114 Renewed October 25, 1935 7 Claims.

This invention relates to a device for detecting the theft of current in electrical supply systems.

In electrical supply systems it is the usual practice to provide a meter which indicates the energy 5 consumed and attempts are often made to bypass such meter to obtain current without registering upon the meter.

The present invention has for one of its objects the provision of means for revealing an attempt 10 to steal current or the stealing of current.

A further object of the .present invention resides in the provision of a device in which the theft of current is impossible without detection.

A further object :of the present invention resides in the provision of a combined safety appliance for interrupting current supply upon a ground being established and for also detecting the theft of current.

A further object of the present invention resides in the provision of a device which will impede and hinder the theft of current upon attempted by-passing of an intermediate meter and more particularly to provide means whereby a single jumper will not afford current supply but in which double jumpers are required to :obtain unauthorized current supply.

A further object of the present invention resides in the provision of means for setting up a maintained indication upon the effective bypassing of a meter which is disposed intermediate a supply circuit and a consumption circuit in an electrical distributor system.

Further and other objects of the present invention will be hereinafter set forth in the accompanying specification and claims and shown in the drawing which shows by way of illustration a preferred embodiment and the principle thereof and what I now consider to be the best mode in which I have contemplated of applying that principle. Other embodiments of the invention employing the same or equivalent principle may be used and structural changes made as desired by those skilled in the art without departing from the present invention and within the spirit of the appended claims.

In the drawing:

Figure l is a somewhat diagrammatic perspective view with portions broken away, illustrating the physical arrangement which my apparatus 50 may assume; and

2 is a wiring diagram showing the parts in normal position.

The present invention relates to features of improvement upon my invention shown and de- 55 scribed in my copending application Serial No.

701,289, filed December '7, 1933, for Safety appliances.

The present invention embodies safety characteristics shown and described in my said copending application and adds thereto features of .5 invention not there shown or described.

Referring first to the wiring diagram shown in Fig. 2, it will be seen that the supply circuit 1110, It! enters the casing H3 at the left. This circuit supplies alternating current and, as is usually 10 the custom, one side It! is grounded. An isolating transformer 36 has its primary winding connected to the supply circuit and its secondary winding 46 is adapted to supply a load through the circuit breaker presently to be described. 15 The load lines 50 and 5| constitute a consumption circuit.

If desired the transformer 36 may be a step-up or step-down transformer, although it need not be; its primary function being to isolate the load lines 505l from ground except through a relay connection hereinafter described.

A circuit breaker 38, when in closed position as shown, enables the secondary winding 46 to supply electrical energy to the load lines 5fl-5I. The circuit breaker 38 is provided with a trip coil 25 52 which when energized, trips the breaker which is then opened by the operation of its usual spring, as shown. The trip coil 52 is connected at one end to one side of the secondary winding 45 and is connected at its other end through the armature and front contact of a relay 37 to the other side of the secondary winding 46. The winding of the relay 3? is grounded at one end, as by being connected to the metallic casing H], which in turn is grounded, and the other end of the winding of the relay 3? is connected to a point of the transformer secondary 46 which is at a potential different from that of either of the load lines 50 and 5!; as shown the point of connection is about mid-way of the secondary winding 46. The circuit breaker 38 is provided with a reset coil 53 connected at one end to one side of the secondary winding it. The other end of the reset coil 53 is connected, through a manually 45 operable normally open key or switch 54, armature 55 and contact 51, to the other side of the secondary winding 46.

As thus far specifically described the appliance shown in the drawing of the instant application is substantially the same in construction and operation as that described in my said copending application. This operation will now be briefly stated.

if either one of the load lines 50, 5| be ground- 5 pany supplying the power.

ed, current flows through the winding of the relay 3'! so as to cause the armature thereof to close on the front contact and thereby energize the trip coil 52. Energization of the trip coil 52 causes the circuit breaker S8 to be automatically opened by its spring, thereby interrupting the supply of electrical energy from the secondary winding 15 to the load lines 50-5! If, as is preferably the case, the relay 3'! is sufficiently sensitive, the circuit breaker 38 will be automatically opened as just described, by even a high resistance ground such as that of a person whose body is grounded and who touches either of the load line wires 55, 5!. By using such a sensitive relay 3"! in the connection shown, the breaker will be automatically tripped when a person whose body is grounded touches either of the load line wires 55, 5|, before any serious damage or even serious discomfort is caused to such person.

After the circuit breaker 38 has been tripped in the manner described, it may be reset by closing the key or switch 54 by manual depression of the button t0, thereby causing the reset coil 53 to become energized to restore the breaker to the normally closed position as shown in Fig. 2. If at this time there is no longer any ground on either of the load line wires 50, 5|, the circuit breaker will remain closed, but if the ground on either of these lines is still present, the circuit breaker will again trip.

A fuller description of the features and construction of operation thus far described will be found in my said copending application.

According to the features of improvement of the instant application there are provided means for indicating or revealing an attempt to steal current by by-passing the usual meter provided in commercial supply systems. While this means may be embodied in specifically different other forms I now prefer the arrangement illustrated and which I shall now proceed to describe.

The metallic casing l0 not only contains the isolating transformer 36, circuit breaker 3B and the relay 3?, but also contains the usual watthour meter, designated M in Fig. 2, and which is provided with the usual dials 65 which are visible through a glass covered window in the door 9 of the casing it] so as to be readable at the usual prescribed times by a representative of the com- A shutter or flag BI is also mounted within the casing l0 and is normally in the position shown in the drawing, in which it is invisible and does not obscure or interfere with reading of the dial 60 (see Fig. l).

The flag or shutter BI is shown pivotally suspended from the arm 62 of a lever pivotally mounted at 53 and whose other arm 64 is normally engaged by a pivoted latch 65 so as to hold the flag or shutter iii in its elevated (dial revealing) position against the action of the spring 6'6. The

pivoted latch t5 has secured thereto the armature 67 of an electr-omagnet 68 so that when the electromagnet is energized the latch 65 will be tripped and the spring 65 will operate the flag or shutter 6| to a position in front of the dials 60 so as to: obscure the same and so as to indicate, as will presently be described, that attempt has been made to steal current.

One end of the electromagnet 68 is connected to the contact iii of the circuit breaker 38 and the other end of the electromagnet is connected to a contact ll of the circuit breaker. The circuit of the electromagnet is normally open at both of the contacts Ni, H but when the circuit break r has been tripped the electromagnet 68 is connected directly across the load lines 50, 5|.

Suppose now with the partsas shown in the drawing an attempt is made to steal current by by-passing the meter M. In order to do this the lines 50, 5| of the consumption circuit must be connected to the supply circuit (at the left) so as to by-pass the meter. Assume that in doing this, the dishonest user first establishes an electrical connection by a jumper 80 from the load line 50 to the ungrounded line I00 of the supply line. Upon the placing in position of this jumper the relay 3! will be energized to trip the circuit breaker 38, and the circuit breaker will be automatically opened. If now an attempt is made to reset or reclose the circuit breaker, by depressing the knob 40 of the reset switch 54, the reset coil 53 will be energized and the breaker will be operated to closed position, but it will not stay in that position if the jumper connection 80 is still present. So long as the jumper connection 80 is present the circuit breaker 38 cannot be held closed. Even though at this time the reset switch 54 is held closed the circuit breaker will intermittently open and close due to the breaking of the reset circuit at the contacts 5551 whenever the breaker moves to closed position. When the circuit breaker 38 is in open position, continuous current supply to the load lines 50-5! cannot be obtained merely with the single jumper connection 80.

Suppose instead of establishing the jumper connection 8!) a jumper connection 8| is first established from the load line 5| to the grounded side It]! of the supply line at the left of Fig. 2.. This causes the relay 3'! to be energized and to cause the circuit breaker 38 to be automatically opened. The effects upon closure of the resetting switch 54 will be the same as described above.

Suppose now that jumper connections are established at both 80 and 8 i. energy will be supplied to the load lines 505l, even though the circuit breaker 38 is open and energy consumption from the load lines 585l will not in these circumstances be indicated by the meter M. However, when the jumper connections 808| are both established to effectively by-pass the meter, the circuit. breaker 38 has become automatically opened and the electromagnet 68 is energized in the following circuit: from the upper side I00 of the supply circuit, through the jumper connection 80, through the load line 50, through the contact 10, through the winding of the electromagnet 68, through the contact I I through the load line 5|, through the jumper connection 8| to the other side ID! of the supply circuit. This energization of the electromagnet 68, as above described, trips the pivoted latch 65 and the flag or shutter 6! is thrown to the position in which it is visible and in which it conceals the dials 60 and indicates by its presence at the window that an attempt has been made to steal current. The flag 6!, it will be understood, remains in this position until manually restored and it further remains in this position even if the jumper connections 80-8l are subsequently removed. Access cannot be had to the interior of the casing l0 without removing the seal 85.

Tampering with the seal is, of course, a serious offense and easily detectable. While I now prefer to employ a seal such as that shown at 85, other forms of casing seals may be employed such as a suitable padlock, combination lock, or the like. In any case the seal is to prevent undetected,

In this case electrical unauthorized access to the interior of the casing l0. Upon authorized entry into the casing II), the flag or shutter Bl may be readily manually restored to the normal position shown.

Summarizing the detecting device indicates not only an attempt to steal current by the bypassing of the meter, but such indication is maintained even after the theft of current has been stopped by removal of the jumpers. The theft indicator cannot be restored by the user, but only by an authorized representative of the power company who must open up the sealed casing to restore the indicator. The circuit connections are such that the theft detector signal does not operate upon the establishment of an inadvertent ground. Stealing of current is hindered by reason of the fact that a single jumper will not provide current supply upon the consumption circuit. Two jumpers are required for such supply. It will therefore be understood that my improved device not only protects a proper user of the consumption circuit, but it likewise protects the power company against improper use by such users. The device further insures that the consumer shall not be compelled to pay for current not usefully consumed, i. e. vagrant currents to ground cannot persist and operate the meter, but must be cleared up. However, any use of unmetered current upon the consumption circuits will be detected and the power company will be apprised of such illegal acts by the meter reader upon the next inspection of the meter, inasmuch as the meter reader cannot read the meter dials with the obscuring shutter in position.

What I claim is:

1. A theft detector for electrical supply systems which includes a supply circuit, a consumption circuit and a meter therebetween, said meter having current consumption indicating means, said theft detecting device comprising indicating means inaccessible to the current user and displaceable from revealing to obscuring position with respect to the current consumption indicating means and means for causing the displacement of said indicating means to obscuring position upon the establishment of a circuit around the meter which affords current supply from the supply circuit to the consumption circuit without traversing the meter.

2. In combination, a supply circuit, a consumption circuit, a meter interposed between said circuits for normally integrating the energy supplied from said supply circuit to said consumption circuit, a circuit breaker for interrupting supply of energy from said supply circuit to said consumption circuit, a theft-indicating device, means operable upon partial by-passing of said meter for automatically operating said circuit breaker, and means operable upon complete bypassing of said meter for causing said indicating device to operate.

3. In combination, a supply circuit, a consumption circuit, a meter interposed between said circuits for normally indicating consumption of energy on said consumption circuit, a circuit breaker for interrupting supply of energy from said supply circuit to said consumption circuit, a theft-indicating device, means operable upon connection of one side of said supply circuit to one side of said consumption circuit for automatically opening said circuit breaker without operating said indicating device, and means operable upon connection of two sides of said supply circuit to two sides of said consumption circuit for operating said indicating device.

4. In combination, a supply circuit, a consumption circuit, a meter interposed between said circuits for metering the energy normally supplied to said consumption circuit from said supply circuit, a circuit breaker for interrupting the supply of energy from said supply circuit to said consumption circuit, means operable upon aocidental grounding of said consumption circuit through a persons body for causing said circuit breaker toopen, a theft-indicating device inoperable upon accidental grounding of said consumption circuit, and means for causing said device to assume theft-indicating condition upon deliberate theft-efiecting by-passing of said meter.

5. A theft detector for an electrical supply system comprising a sealed casing, a meter within said casing with dials visible through a window therein, an indicating shutter normally disposed in non-obscuring relation with respect to the dials and displaceable to obscuring relation to said dials, and means Within said casing and automatically operable upon attempted theft of current and upon the effective by-passing of the meter for bringing about a displacement of said indicating means to a position in which the dials are obscured.

6. A combined theft detector and safety supervisor control device for electrical distribution systems, comprising means for automatically establishing open circuit relations upon an inadvertent ground being established, means for setting up a maintained indicator of an attempted theft of current upon attempted efiective bypassing of a meter, and means for preventing operation of said last named means upon the operation of the first mentioned means upon the establishment of inadvertent grounds.

7. In combination, a supply circuit, a consumption circuit, a meter interposed between said circuits for measuring energy normally supplied from said supply circuit to said consumption circuit, means operable upon by-passing of said meter for interrupting the normal supply of energy from said supply circuit to said consumption circuit, means operable by the user of the consumption circuit for causing normal connections between said supply circuit and consumption circuit to be re-established when the bypassing has been removed, a theft-indicating device, means operable upon complete by-passing of said meter for causing said indicator to become operative, and means for preventing the user of said consumption circuit to restore said indicating device to normal position after it has been operated to indicating position.

L ALAN SHARP.

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