Did you buyexplosion-proof magnetic starter like this?
Nature of explosion-proof magnetic starter
Under specified test conditions, the ratio of the minimum ignition current of gas or vapor explosive mixtures to that of methane explosive mixtures. China classifies gas and vapor hazardous substances into Class IIA, IIB, and IIC based on the minimum ignition current ratio. Minimum ignition current ratio ≤1.0, >0.8 is Class IIA; ≤0.8, >0.45 is Class IIB; ≤0.45 is Class IIC. For example, ethane, ethylene, and acetylene are Class IIA, IIB, and IIC hazardous substances respectively.
Explosion-proof magnetic starter structural requirements
1. The main cavity of the starter is of flameproof type, and the terminal cavity is of increased safety type.
2. The electrical clearance of the starter is not less than 6mm, and the creepage distance is not less than 10mm.
3. The housing material of the starter is made of cast aluminum alloy with magnesium content not greater than 6% (mass percentage).
4. All fasteners of the starter must have measures to prevent self-loosening.
5. All ferrous metal parts of the starter must have anti-rust measures, and the surface must not have coating peeling.
6. The starter should be equipped with grounding screws, internal grounding screw M6, external grounding screw M8, and marked with grounding symbol "〨".
7. The starter housing should have a clear, permanent raised mark "Ex" in a conspicuous place.
8. For Class IIB, the flameproof joint width L≥12.5, l≥8, joint gap/diametral clearance ic≤0.15;
For Class IIC, the flameproof joint width L≥25, joint gap/diametral clearance ic≤0.15, and the average surface roughness Ra of the joint surface does not exceed 6.3μm.
9. The transparent part of the starter observation window is directly bonded in the cover opening, and the shortest path through the adhesive joint from inside to outside of the flameproof enclosure is not less than 10mm.
10. The flameproof joint surface of the starter is coated with 204-1 displacement anti-rust oil.
11. The outer surface of the starter housing is coated with light gray powder paint.
Explosion-proof magnetic starter product features:
1. Cast aluminum alloy shell, surface sprayed with plastic.
2. Composite structure, the shell is increased safety type, with buttons inside, which are flameproof components.
3. Both steel pipe and cable wiring are acceptable.
