POWDER FILLED TYPE “q” PROTECTION. [ q ]
This protection technique is governed by IEC 60079-5
EPL associated with [ q ] = Gb or Mb
This standard applies to :-
- Electrical Equipment
- Parts of Electrical Equipment
- Ex Components
- A rated supply current of less than or equal to 16 amps
- Rated supply voltage of less than or equal to 1000 Volts
- rated power consumption of less than or equal to 1000 Watts
Powder filling originated in France as a concept in 1954, but it was not generally recognized as an Ex Protection concept until the publication of IEC Standard 60079-5 in 1967. This protection method is typically used only for small transformers, capacitors and on electrical components that have no moving parts. The protection consists of a sealed enclosure (normally with a vent) containing quartz sand (the origin of the “q” description), powder or glass beads.
Electrical equipment and Ex components protected by powder filling “q” may contain :
- electronic circuits
- protection fuses
- intrinsically safe electrical apparatus,
- associated electrical apparatus
Example : Electronic Ballast for Hazardous Area Fluorescent Fixture (Type Ex ed)
Another Example , 100 Watts Power Supply in Aluminum Enclosure with non-metallic Ex e Cable Glands for external connections through cables.
(Protection : Ex eq)
The Filling Material
Filling material is Solid quartz or Solid Glass Particles. Filled completely.