Is theexplosion-proof magnetic starter you bought like this?
Nature of Explosion-Proof Magnetic Starter
Under specified test conditions, the ratio of the minimum ignition current of a gas or vapor explosive mixture to the minimum ignition current of a methane explosive mixture. China classifies gas and vapor hazardous substances into Class IIA, IIB, and IIC based on the minimum ignition current ratio. A ratio ≤1.0 and >0.8 is Class IIA; ≤0.8 and >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 a magnesium content not greater than 6% (by 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 any peeling of the coating.
6. The starter should be equipped with grounding screws: internal grounding screw M6, external grounding screw M8, and marked with the grounding symbol "〨".
7. The housing of the starter should have a clear, permanent raised mark "Ex" in a conspicuous place.
8. For Class IIB, the flameproof joint width L≥12.5mm, l≥8mm, joint gap/diametral clearance ic≤0.15mm;
For Class IIC, the flameproof joint width L≥25mm, joint gap/diametral clearance ic≤0.15mm, and the average surface roughness Ra of the joint surface does not exceed 6.3μm.
9. The transparent part of the observation window of the starter is directly bonded in the opening of the cover, and the shortest path from inside to outside of the flameproof enclosure through the adhesive joint is not less than 10mm.
10. The flameproof joint surface of the starter is coated with 204-1 displacement type 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, shell is increased safety type, with built-in buttons. It is a flameproof component.
3. Suitable for both steel pipe and cable wiring.
