CN114930729B

CN114930729B - Luminous indicator device for mining cable connector and mining cable connector including the luminous indicator device

Info

Publication number: CN114930729B
Application number: CN202080026476.6A
Authority: CN
Inventors: 塞萨·古斯塔沃·利维洛·皮扎罗
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-01-20
Filing date: 2020-01-20
Publication date: 2025-01-10
Anticipated expiration: 2040-01-20
Also published as: WO2021150128A1; PE20211678A1; CN114930729A; CA3134114A1

Abstract

The present invention relates to a mining cable connector including a light-emitting LED indicator device and a light-emitting LED device indicating the status of a pilot-ground loop, wherein the light-emitting indicator device includes a GC terminal connected to a fuse; the output node of the fuse is connected to a transient voltage suppressor (TVC) diode and a driver, and the driver is connected to a lamp, specifically to a light-emitting diode (LED); then, the output node of the LED lamp is connected to the TVS and GND terminals, wherein the pilot terminal and the ground terminal of the loop of the present invention are suitable for being connected to the control (GC) core and the ground (GND) core of the mining cable through a connector and a junction box mechanically fastened to the connector.

Description

Light emitting indicator device for a mining cable connector and mining cable connector comprising the same

Technical Field

The invention belongs to the technical field of cable fault detection devices, and particularly relates to a luminous LED indicator device for a mining cable connector.

Background

In the prior art there is a patent document US4228475A entitled "ground monitoring system" published on 10 th month 14 of 1980, which describes a device comprising elements of relays, transient voltage suppressors, zener diodes, band pass filters, drivers, transformers, generation of detection signals, current sources etc. which help to detect and correctly connect a ground cable to a power cable of the type commonly used in open-air mining sites, which establishes a complete conductive loop between one or more ground cores and a ground check cable or the control core of the cable. However, this precedent discloses a fixed position pilot-ground loop monitoring relay (e.g. in a power distribution substation) that injects a time-varying signal at a frequency of 1KHz, i.e. it does not refer to a device that shows the status of the pilot-ground loop and is portable (as it is mounted on a connector). The relay of the preceding example performs the function of detecting when a fault occurs in the circuit and commanding the switch to open to cut off the power supply through the cable, while the luminous indicator of the invention does not inject any type of signal into the circuit nor open any cutting element. Furthermore, this precedent does not allow to connect more than one light-emitting indicator on the same cable extension, so it is impossible to know the status of the pilot-ground loop in the field, let alone that it is not advantageous to determine the location (spot) of the fault.

It should be clear that throughout this document "connector" or "mining cable connector" will be understood as any connection means between mining cables, such as couplers, splitters, etc., for use in open fields, pits or tunnels. Likewise, the terms "ground", "GND" and "G" are used to refer to electrical connections to the system ground wire core, while the terms "lead", "ground check" and "GC" are used to refer to electrical connections to the control wire core of the system.

Disclosure of Invention

The present invention has been made to solve the above-described problems. The invention relates to a mining cable connector comprising a light emitting LED indicator device, and a light emitting LED indicator device for displaying the status of a pilot-ground loop and adapted to be coupled to low and medium voltage mining cable connectors, wherein the light emitting indicator device comprises GC terminals connected to a fuse, the output node of which is connected to a transient voltage suppressor diode (TVS) and a current controller (driver), which is connected to a lamp, in particular to a Light Emitting Diode (LED), the output node of which is then connected to TVS and GND terminals, wherein the pilot and ground terminals of the loop of the invention are adapted to be connected to the control (GC) core and the Ground (GND) core of the mining cable by means of a connector and a junction box mechanically fastened to said connector.

Preferably, the cable connects each terminal of the loop to the junction box, which is then connected to the lead and ground feeds of the connector using a cable wrapped with a synthetic fiber braid, preferably glass. The synthetic fiber braid coating is important because it increases the tensile strength of the junction box-feeder cable, which is relatively thin and may be subject to some mechanical stress during assembly and disassembly of the connector. Finally, these connectors are connectors that are in direct electrical contact with the control wire core and the ground wire core of the trailing cable.

The loop is powered by a direct current signal from the pilot monitor relay to the loop through the GC terminal and the GND terminal. In normal operation, the resistance of the fuse is negligible (short circuit), while the resistance of the TVS is very high (open circuit). Thus, all power supplies can be said to be supplied to the current controller and the LEDs. The current controller includes a constant current source that is implemented with the active and passive components required to set the current so that the LED is significantly lit without affecting the proper operation of the pilot monitor relay.

If there is an AC voltage between the GC terminal and the GND terminal of the loop and of sufficient magnitude to place the TVS in its polarized state, the TVS will change from its low conductive state to a high conductive state. This current will flow through the fuse and cause it to open (open). Thus, the ac voltage will not damage the current controller or the LED lamp.

The invention has the following technical effects:

the illuminated indicator device is directly powered by the direct current signal of the terminated pilot monitoring relay, so it does not require any additional power supply to operate.

The advantage of the illuminated indicator device is that it is placed directly in the path of the field, mining cable, as it is part of the connector. This facilitates the localization of wiring, connectors and faults.

The combination of the TVS and the fuse protects the current controller and the LED lamp from undesired external ac voltages. The TVS will generate enough current to open the fuse.

The light-emitting indicator device uses a constant current source to power the LED lamp, which makes it easier for the light-emitting intensity of the LED to remain constant in the face of a direct-current voltage variation occurring in the ground-lead line.

Drawings

As a complement to the description of the invention and to facilitate the understanding of the invention, the present description is accompanied by a set of two figures as a constituent part thereof, in which the following preferred forms of the invention are described in illustrative and non-limiting detail:

Fig. 1 shows a schematic view of a light emitting LED indicator device and the connections between its components.

Fig. 2 shows three light-emitting LED indicator devices, which are connected between the monitoring relay circuit of the pilot-ground circuit and its terminals.

List of reference numerals:

a monitoring terminal relay of a pilot-ground loop;

2, leading/grounding inspection wires in the mining trailing cable;

3, grounding wire cores in the mining trailing cable;

Monitoring a relay terminal;

5, a protection fuse of the LED indicator;

A transient voltage suppressor diode (TVS);

7, a driver for supplying power to the LEDs;

8, light Emitting Diodes (LEDs);

Luminous LED indicator device (LED indicator).

Detailed Description

More specifically, the fuse 5 may be a delay type (delay type) in which an off-current is 100mA, or it may be a PCB-mounted type. The time delay fuses may be replaced with conventional fuses or with self-healing fuses (polymer positive temperature coefficient (PPTC) fuses). The off-current may be changed to any other value as long as the associated TVS 6 is capable of conducting the current in the presence of a defined alternating voltage.

TVS 6 may be bi-directional and its breakdown voltage v_br may have at least the same value as the external voltage supported by the associated pilot monitoring relay 1, with an indeterminate duration. The TVS 6 may be replaced by a varistor as long as it is capable of carrying the cut-off current of the associated fuse in the presence of a defined alternating voltage.

The current controller (driver) 7 uses constant current sources and passive and active components required for configuring it, which can be done by a person skilled in the art. The constant current source may be of the integrated circuit type or may be implemented as a discrete component. The current value to be configured will depend on the magnitude of the direct current injected into the pilot-ground loop by the associated pilot-monitoring relay 1. For example, for an injection current of 25mA, a constant current source of 300uA is configured. On the other hand, a DC-DC converter having a constant current output, which can supply the same current as the constant current source, may be used instead of the constant current source. Furthermore, the DC-DC converter must be in close proximity to the cable and the power conductors of the connector to operate under electromagnetic conditions.

The Light Emitting Diode (LED) 8 used is preferably low current consumption, wherein the light intensity corresponds to at least 500mcd when the positive polarity current is 2 mA. Preferably, the color of the LEDs should be contrasted with the color of the connector, for example, if the connector is orange, a blue or green LED may be used.

The present invention is suitable for connection to the pilot monitor relay 1. Although this relay is not a direct part of the invention, it plays an important functional role and must therefore be mentioned here. The relay serves as the power and pilot-ground loop status signal of the present invention. The relay must work with the terminal 4 (zener diode, normal diode, impedance, etc.) and must inject a direct current into the pilot circuit. It must be able to supply a minimum voltage of 5VDC and a minimum current of 25mA. The monitoring relay 1 performs two functions, power and loop status signals. The power supply function may be replaced by any other power means, such as a battery/accumulator, a system of feeders connected to connectors, or an energy harvesting/electromagnetic energy capturing system.

Such a luminous indicator device 9 may be provided for public use, pre-installed in a connector for a mining cable, as well as it may be provided as part of a set of connector sub-parts (aluminium cap and copper connector) for use in situations where customers require retention of the connector already in place but wish to add a lead LED light device.

Fig. 1 shows the elements of the luminous indicator device 9 and the connection of the luminous indicator device 9 to the ground-pilot relay circuit. It will be appreciated that the mining cable connector is arranged alongside the light-emitting indicator device 9.

Fig. 2 shows an example of an embodiment of the invention in which it is illustrated that all light emitting LED indicator devices (LED indicators) will be on when the pilot-ground loop is in good condition and the monitoring relay is on. If a fault such as a segment/break/loss of continuity occurs in the cable portion designated as fault 1, all LEDs will be turned off. On the other hand, if such a fault occurs at the fault 3 location, only the LED indicator 3 will be turned off, while the indicators 1 and 2 will remain on. If a short circuit fault occurs between ground and the pilot circuit, all LED indicators will be turned off. Table 1 summarizes the status of each LED for two possible fault types in the loop at different locations.

All LEDs will be turned off only if the fault occurs at the fault 1 location, or if the fault is a short between ground and the pilot loop. Finally, this explains how faults in the pilot-ground loop can be more easily located by using multiple LED indicators.

Claims

1. A light-emitting indicator device for displaying the status of a pilot-ground loop and suitable for use in a mining cable connector, characterized by comprising a pilot terminal connected to a fuse, an output node of the fuse being connected to a transient voltage suppressor diode and a current controller, the current controller being connected to a light-emitting diode, and finally an output node of the light-emitting diode being connected to the transient voltage suppressor diode and a ground terminal.

2. The light-emitting indicator device of claim 1, wherein the fuse is a delay type with an off-current of 100 mA.

3. The light emitting indicator device of claim 1, wherein the fuse is a polymer fuse having a positive temperature coefficient.

4. The light-emitting indicator device of claim 1, wherein the transient voltage suppressor diode is replaced by a piezoresistor.

5. The light-emitting indicator device according to claim 1, wherein the current controller employs a constant current source, or a DC-DC converter having a constant current output and adapted to deliver the same current as the constant current source.

6. A mining cable connector is characterized by comprising a junction box arranged in the connector, wherein a luminous indicator device for displaying states is connected to a pilot-ground loop on the junction box, the luminous indicator device comprises a pilot terminal connected with a fuse, an output node of the fuse is connected to a transient voltage suppressor diode and a current controller, the current controller is connected to a light emitting diode, and finally, the output node of the light emitting diode is connected to the transient voltage suppressor diode and a ground terminal.

7. The mining cable connector of claim 6, wherein the junction box is connected to the connector's lead and ground feed lines by cables wrapped with a synthetic fiber braid.