Design Of Mine Flameproof And Intrinsically Safe Four-loop Combination Switch

Flameproof switch which has single control function has deeply restricted the development speed of the coal mine automation. Mining enterprises have urgently demand of flameproof switch combination to control downhole electrical equipment. This article takes the new products of The Huainan ladder of Electronic Science and Technology Co., Ltd as the basis, aims at demand of the enterprise, and newly designs mine explosion-proof and intrinsically safe four loop combination switch.Motor plays a vital role in the process of coal mine production. Whether coal mine electrical equipment is functioning properly, directly impacts on the safety of coal production. Damage of motor in electrical equipment is the major factor that affects the production efficiency of mining enterprises. So that this protection circuit is necessary to the combination switch. This article designs major loop, control loop and protective circuit respectively. Major loop supplies power to shearer loaders, reversed loaders, and emulsion pumps; And both control loop and protective circuit offers control and protection to these equipments. In protective circuit, protection of overload, short circuit, leakage, broken phase imbalance is designed.According to the control requirements of the user’s, this article analyses and designs single independent control, stand-alone two-speed control, stand-alone hybrid control and dual two-speed control of four loop combination switch. Consider that the poor working conditions of underground coal mine, flameproof switch control can not meet the need for efficient production. This article takes programmable controller as the core of combination switch, makes the control and protection of charged device come true, such as leakage locking, leakage protection, overload and short circuit, the broken phase imbalance and under voltage over voltage protection function and the communication signal upload function. This makes combination switch with advantages of a high degree of intelligence, stable performance and reliable action.This article supports the GOT1000series GT1155HS-Q models and Chinese LCD touch screen with programmable controllers, designs main menu and parameter settings as well as fault protection screen of the four-loop combination switch by the GT-designer2software, and corresponds the address with PLC, and turns out to realize the switch, parameters, and the type of fault display and memory function. Interactive features greatly enhance efficiency of determine fault and troubleshooting. Complete self-test, self-diagnosis and fault simulation test function can easily check for the protection and control system, whether it is normal or not.Flameproof enclosure is the essential requirements to anti-explosion of the four-loop combination switch. This article designs enclosure of the four-loop combination switch, which refers to the national explosion-proof electrical enclosure design standards.