CN2308904Y - 3.3KV high voltage insulation detector - Google Patents

Abstract

The utility model relates to a China initiated high voltage insulation detector used in power feed switches and magnetic starters in 3.3KV power supply systems. The utility model not only can be used in explosion-proof switches under coal mine wells, but also can be used in ground general type switches. Parameters of every single component can be slightly changed. Moreover, the utility model can be used in 6KV, 10KV power supply system switches. When the ground insulation resistance of a load power line drops below a permitted level, the utility model mainly can close and lock the switches for preventing electric leakage accidents. The utility model has the major technical principle that 3.3KV DC is applied to a dynamic load end, a sampling section is used for collecting resistance signals of electric leakage, and a protection unit is used for identifying the signals and send stop switching signals and fault signals. Moreover, the faults can be recorded, and the faults can be eliminated through maintaining load cables.

Description

3.3kV High-Voltage Insulation pick-up unit

The utility model 3.3kV High-Voltage Insulation pick-up unit relates to underground mine use flame-proof mine feeding switch, the universal feeding switch of magnetic starter and ground, the earth leakage search/lockout type insulation detection device in the magnetic starter.

At present; known earth leakage search/lockout type insulation detection device; it detects voltage and is the 9-40V DC voltage; take out by detecting the loop power line insulation against ground resistance signal of will load, send instruction, when insulation resistance drops to setting when following through protecting actuating circuit; send steering order; make feeding switch or trigger locking, i.e. switch fail to start reaches protection cable and consumer safety.

The technical matters that above-mentioned earth leakage search/lockout insulation detection device exists is: the insulation resistance that detects with low pressure can not be equivalent to the insulating resistance value of power line under the real work voltage condition, and rising along with power supply grid voltage, this difference is also just big more, thereby after appearing at the tripping operation of switch emerged in operation leak current fault, after the earth leakage search/lockout insulation detection device drops into, detect state of insulation and but be normal, starting causes cable to puncture over the ground with subscriber equipment to damage once more.

Increase along with installed capacity under the coal mine, supply voltage is elevated to 3.3kV by 1140V, China has listed this time plan in national great technological transformation project, according to the electric power system requirement of external 3.3kV colliery, in feeding switch and the trigger except the earth leakage search/lockout pick-up unit will be arranged, also must add 3.3kV High-Voltage Insulation pick-up unit, promptly use the detection voltage with the supply voltage equivalence to detect power line insulation against ground resistance, avoid the expansion accident, guarantee power supply safety, and this kind device still belongs to blank at home.

The utility model 3.3kV High-Voltage Insulation pick-up unit purpose be feeding switch or trigger leakage tripping once after, earth leakage search/lockout detects and detects again under the failsafe situation, this device comes into operation, and the time-delay measuring ability arranged, prevent because the power line malfunction that causes of distributed capacitance over the ground, when power line insulation against ground resistance≤1M Ω, realize locking, and can external demonstration light emitting diode, the detection operating state shown.

The purpose of this utility model is achieved in that

1. detecting power supply is the 3.3kV DC voltage;

2. detect electric current and be not more than 2mA;

3. form artificial asterism by silicon stack and receive the living load line, through the transformer secondary winding, sample resistance connects the earth and forms the detection loop;

4. sampled signal enters and protects assembly to differentiate;

5. external input power supply is AC110V, forms through test button switch auxiliary contact reset button and detects controlling unit;

6. export one group of normally opened contact and receive switch control unit realization latch switch function, export a light-emitting diodes interface tube and show fault actions.

Design feature of the present utility model:

1. critical piece transformer, the silicon stack assembly, sampling assemble, the protection assembly all adopts envelope to irritate pattern, can be moistureproof effectively, the protection electric property.

2. adopt adjustable timing relay, can select different delay times according to the length of load cable;

3. externally the control line connection realizes by a round edge connector, and is easy to use;

4. whole device is arranged on 250mm * 300mm steel plate, and volume is less.

The electrical schematic diagram of the utility model device is seen shown in Figure 1, and its principle of work is as follows:

Silicon stack V1, V2, V3 form artificial asterism, and receive on the living load line, K1 is the adjustable time relay, its contact control sampled signal is input to protection assembly M, T1 is a power transformer, R1, R2, R3, R4 and C1 form sampling assemble, detect power supply through sampling assemble, ground end PE, power line insulation against ground resistance, power line U, V, W, silicon stack constitute direct current 3.3kV and detect the loop, form detection signal voltage on resistance R 4; Detection link, memory link and execution link that protection assembly M circuit is formed by rectification link, voltage stabilizing link, sampling link, benchmark link, by cmos circuit are formed.

Only drop into when stopping at feeding switch or trigger for guaranteeing that High-Voltage Insulation detects, the input power supply is input to transformer through feeding switch or the auxiliary normally closed contact QF of trigger.

When pressing test button SB; the K1 time-delay several seconds inhales; transformer T1 has; through V1; V2; 3.3kV detects the living load line after the V3 rectification, greater than 1M Ω, then protects the still adhesive of assembly M repeat circuit as insulation; its output contact closure; then unclamp test button, switch can close a floodgate or start, if insulation resistance drops to 1M Ω and when following; assembly M action; relay discharges, and circuit also can be remembered fault, and then output contact is opened; the outside connected switch control module guarantees that switch can not close a floodgate or start this moment; after having only the fault of reparation, press external reset button SR, switch just can put into operation.After the assembly action, external light emitting diode HL shows that with bright cable has fault.

In protection assembly M, a governing loop is set, can changes working value easily.

Change silicon stack and transformer parameter in the utility model device, promptly can be used for going in 6kV or the various switches of 10kV electric power system, equipment can be used for again in the universal equipment of ground under the promptly available coal mine.

The utility model 3.3kV High-Voltage Insulation pick-up unit structural arrangement is seen Fig. 2, wherein:

1--installs base plate

2--high-voltage connection seat

3--silicon stack asterism assembly

The 4--connecting terminal block

The round edge connector of 5--

6--detects power transformer

7--protection assembly M

The 8--time relay

The 9--sampling assemble

Claims (3)

1. one kind is used for explosion-proof feeding switch under the coal mine or trigger, also can be used for the 3.3kV High-Voltage Insulation pick-up unit of ground General Electric equipment; form by protection assembly 7, silicon stack asterism assembly 3, detection power transformer 6, sampling assemble 9, round edge connector 5, high-voltage connection seat 2, the time relay 8; it is characterized in that: R1, R2, R3, R4 and C form sampling assemble; V1, V2, V3 form artificial asterism and connect with living load, and the protection assembly M and the time relay 8 fit together.

2. according to claim 1,3.3kV High-Voltage Insulation pick-up unit is characterised in that altogether described detection power transformer 6, silicon stack asterism assembly 3, sampling assemble 9, protection assembly M all adopt envelope to irritate pattern.

3. require described 3.3kV High-Voltage Insulation pick-up unit according to right 1, it is characterized in that adopting the detection and the memory circuit of cmos digital circuit composition, and have link and the fault reset function that to adjust working value.

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