Flameproof Limit Switch

Product Details:

“SAIEX” Flameproof Limit Switch is an electromechanical position-sensing switch enclosed in a flameproof (explosion-proof) housing, designed for use in hazardous areas where flammable gases or vapors may be present.

Its purpose is to:

• Detect end position, presence, or movement of a mechanical part
• Safely switch electrical circuits without igniting the surrounding explosive atmosphere
• Contain any internal spark or explosion within the enclosure

“Flameproof” means the enclosure can withstand and contain an internal explosion and prevent flame propagation outside.

Various Names (Equivalent Terms): Flameproof Limit Switch, Explosion-Proof Limit Switch, Ex d Limit Switch, Hazardous Area Limit Switch, ATEX Limit Switch, IECEx Limit Switch, EEx d Limit Switch (older IEC term), Heavy-Duty Industrial Limit Switch, Position Limit Switch (Flameproof Type)

Gas Group: IIB, Temperature class: T6, Zone: 1/2 & 21/22

IP Protection: IP 65 as per IS/IEC 60529: 2001

Colour: Epoxy Grey 631 (Other option Pebble Grey 7032, 7035 & Pure White 9010)

Gasket: Endless Molded Neoprene (‘O’ Ring)

MOC: Cast Aluminium Alloy LM-6

Earthing: 1 nos inside & 2 nos Outside

Electrical Maximum Rating: upto 10Amp, 240V AC/110VDC

Marking Plate: (Ex db IIB T6 Gb) (Ex tb IIIC T85⁰ Db)

Cable Entry Size: M20, ½” NPT, ¾” ET

Cable Entry Nos: 1 nos

Element: 1nos NO + NC (Normally Open & Normally closed)

Accessories: With or Without Cable Gland

CERTIFICATES: BIS | CIMFR | PESO

STANDARDS: IS/lEC 60079-0:2017 | IS/lEC 60079-1:2014| IS/lEC 60019-31:2013

How It Works

Construction Features

• Robust metal enclosure (die-cast aluminum or stainless steel)
• Precisely machined flame paths
• Mechanical actuator:
  • Plunger
  • Roller lever
  • Rotary lever
  • Fork or cam
• Internal snap-action micro switch
• Explosion-proof cable entry (Ex d gland)
• High ingress protection (IP65 / IP66 / IP67)

Working Principle

1. A moving machine part (cam, shaft, valve stem, door, etc.) contacts the switch actuator.
2. The actuator mechanically moves the internal mechanism.
3. The internal contacts:
   • Open or close an electrical circuit
   • Generate a small spark during switching
4. Any spark or ignition:
   • Is fully contained inside the flameproof enclosure
   • Hot gases cool through flame paths
   • No ignition reaches the external hazardous atmosphere

Where Are Flameproof Limit Switches Used?

They are used wherever position sensing or safety interlocking is required in explosive atmospheres.

Typical Industries

• Oil & Gas
• Petrochemical plants
• Chemical processing
• Refineries
• Power generation
• Fertilizer plants
• Paint & solvent handling units
• Pharmaceutical plants (solvent zones)
• Mining

Common Applications

• Valve position indication (open/close)
• Conveyor end-position detection
• Door and access-panel interlocking
• Crane and hoist travel limits
• Damper position monitoring
• Machine safety interlocks
• Emergency shutdown systems (ESD)

Additional Information:

• Production Capacity: 1000 per month
• Delivery Time: Depend on Quantity