Cranes in use once after a power failure, they can lead to transmission duct spark, and collector of damaged equipment. If you want to improve this problem, on the one hand increasing collector brush chamfered and polished while increasing collector spring between the two brush strength, elasticity, and ensure that springs back easily.
The other hand, deepened and strengthened set of electrical spring seat as far as possible, ensure the brush of the spring work in not prone to the phenomenon. There is on the one hand, it is to ensure the safety of two wire connection connection block must have chamfers, ensure current collector for smooth transition. Meanwhile, to assure the safety wire used must be standard operating, maintenance and repair equipment, reducing the risk of its failure.