Hello Sirs,
what is different between equipments classification EExde with EExed in HAZARDOUS area?

 

Rule 18-052 Ontario Electrical Safety Code Page 98

Ex or EEx - The 1998 OESC accepts both Ex and EEx on a product, these symbols basically mean the same . ('Ex' is the IEC symbol for hazardous location equipment and the 'EEx' simply designates that equipment also meets the requirements of the European (CENELEC) Standards

de -Next is the type(s) of protection used.

- May Have Multiple Symbols.

- Usually Most Important First

IIA - Indicates Apparatus Location and Gas Group

T3 -The final designation is the temperature code.

In the case of a control station, the enclosure (Main component) is increased safety "e" and the control devices (push button, Pilot light, etc) are flame proof "d", therefore "ed" would appear.

In the case of a stand alone control device (e.g. Push button) the contact chamber (main component) is flameproof "d" and the connection terminals are increased safety "e" therefore "de" would appear.

Tony Moscioni
Electrical Inspector
Electrical Safety Authority

 

> Hello Sirs,
> what is different between equipments classification EExde with EExed in HAZARDOUS area?

I'm from Australia and we use a different system of certification where we only look at the primary from of protection for assessment, so don't quote me on but I believe it comes down to the first letter being the PRIMARY form of protection. In the case of Eex'de', Ex'd' would be the primary form of protection, with secondary components being protected by Ex'e'. Vice-versa with Eex'ed' where Ex'e' is the primary. This appies to other "dual or multiple certified" equipment, an example would be say a Lucifer Eex'me' solenoid where Ex'm' encapsulation of the coil in epoxy is the first line of defence, and then as the metal terminals are exposed the unit is wrappedd in an Ex'e' enclosure to protect them. I came across a telephone the other day that was certified Eex 'edmq(ib)'!! Usually all it is telling you is that it has more than one component, and that they are certified under a particular form of explosion protection. Hope it helps...

 

There is no difference, both are equipment classifications with the same protection systems. Area classifications are Zone 0, Zone 1 , Zone 2, Zone 10 and Zone 11.

 

MTL gives out a good comparison chart , I believe available in pdf format for free at their website.

Regards,
Anand

 

Dear anand,

Can you please give the full name of MTL or their website name.

Regards.

arif

 

Try

http://www.mtl-inst.com

Regards,
Rocky

 

Their web site is:
http://www.mtl-inst.com/

Bill Mostia
=====================================================
William(Bill) L. Mostia, Jr. P.E.
Partner
exida.com
Worldwide Excellence in Dependable Automation
[email protected](b) [email protected](h)
www.exida.com 281-334-3169
These opinions are my own and are offered on the basis of Caveat Emptor.

 

I recommend that you go through a 100 slide powerpoint presentation on HAZARDOUIS AREA CLASSIFICATION that is uploaded in SIRI web site.

http://siri.uvm.edu/ppt/hacsreejith/

Please let me know your comments.

Sreejith
India

 

Hello Sirs,

There is no difference with the protection concepts e.g. two protection concepts, one being EEx d the other being EEx e. Normally the main concept is shown first, therefore in the case of EEx de, the main concept is Ex d. The classification are Zone 0,1 and 2 for gas, vapours and mists and zone 20, 21 and 22 for dusts (IEC). In europe ATEX is now in use.