Product details

Overview

This standard specifies the model specifications, requirements, test methods, inspection rules, marking, packaging, transportation, and storage of GKG - □ /10 (6) general high-voltage switchgear for mining.

This standard is applicable to GKG - □ /10 (6) mining general high-voltage switchgear used in non coal mining and other similar underground industrial production departments. Manufacturing and inspection of switchgear.

Basic parameters

◆ Rated voltage: 10 (6) kV;

◆ Rated current: 1250 (1100, 1000, 880, 800, 630, 550, 500, 400, 300, 250)

Basic parameters of circuit breaker

Rated short-circuit breaking current: 31.5kA (effective value)

Rated short-circuit closing current: 80kA (peak)

Rated short-time withstand current: 31.5kA (effective value)

Rated peak withstand current: 80kA (peak)

Rated short-circuit duration: 4s

3.5 Main protection functions of switchgear:

a) Short circuit protection b) Overload protection c) It also has functions such as fault memory, fault query, and self check.

Technical requirement

4.1 General Requirements

4.1.1 The switchgear shall comply with the requirements of this standard and be manufactured according to the drawings and

technical documents approved by the designated inspection unit of the country.

4.1.2 In addition to meeting the technical requirements, it should also comply with the provisions of GB/T12173-2008 standard.

4.2 Environmental conditions

The switchgear should be able to operate normally under the following conditions:

a) Altitude: 1000m;

b) Environmental temperature:- 20℃ ~40℃；

c) Relative humidity: 95%;

d) In a gas or steam environment that does not damage insulation;

4.3 Shell

4.3.1 Materials

The outer shell of the switchgear is made of 2.5mm thick cold-rolled steel plate.

4.3.2 Strength

The material of the switchgear shell shall comply with the provisions of Chapter 8 of GB3836.1-2010 and shall withstand an impact strength impact test of 1kg/7J.

4.3.3 Protection level

The protective capability of the switchgear shell should comply with the provisions of Article 4.9 of GB3836.3-2010, and the protective capability should not be lower than IP54.

4.3.4 Surface temperature

The surface temperature of the switchgear shall not exceed 85 ℃ in accordance with the relevant provisions of GB/T12173-2008;

The operating handle and handwheel should not exceed 60 ℃ .

4.6.2 Creepage distance complies with the provisions of Article 4.4 of GB3836.3-2010. The distance is shown in Table 2 

Determination of pollution level 3, material group I, and rated working voltage for switchgear;

4.7 Grounding connectors

The switchgear should be equipped with internal and external grounding devices that comply with the provisions of Chapter 15 of GB3836.1-2000, and marked with (equipped with) grounding signs.

4.8 Interlocking

4.8.1 All switch handles of the switchgear should be self-locking after cutting off the power supply to prevent accidental operation

4.8.2 The switchgear should be equipped with a warning sign that reads' No opening with live power '

4.8.3. The opening and closing of circuit breakers and grounding switches should be smooth and unobstructed; When the circuit breaker is in the closed position, the handcart cannot be pulled out; Circuit breakers and grounding switches shall not be closed simultaneously.

4.9 Temperature rise

4.9.1 The allowable temperature rise at the interconnection of conductors in mining low-voltage switchgear should not exceed the provisions in Table 3.

4.10 Overcurrent protection test

4.10.1 Overload protection shall comply with the provisions of Table 4 and have alarm function

4.10.2 When the current exceeds the short-circuit protection set current (4Ie~10Ie), the circuit breaker immediately opens for protection, with an action time not exceeding 100ms.

4.11 Self check and fault query function: The switchgear should be able to perform self check through the self check circuit and have fault query function.

4.12 Main circuit resistance test: The contact resistance of the main circuit should not exceed 400 μ Ω., The difference before and after temperature rise should be less than 10%.

4.13 Insulation level as shown in Table 5

4.14 The wet heat performance shall comply with the requirements specified in Appendix C of GB3836.1-2010, with a severity level of high temperature of 40 ℃ and a wet heat test cycle of 2Id.

4.15 Breaking and closing ability test, the short-circuit breaking ability should comply with the provisions of Article 6.104 of GB1984 and meet the requirements of Article 3.4 of the standard mentioned above.

Note: 1. Control circuit 2kV.

2. The main circuit and control circuit of the switch must be able to withstand the AC 50Hz power frequency test voltage without breakdown or flashover for 1 minute.

Table 5

4.16 Short time withstand current and peak withstand current test

The rated short-time withstand current shall comply with the provisions of Article 6.6 of GB/T 11022 and meet the requirements of Article 3.4 of the standard mentioned above.

Note: "O" indicates the items that need to be inspected, "-" indicates the items that do not need to be inspected, and "*" indicates that only the power frequency withstand voltage is tested at the factory.