Class I Div I, II, or not at all?

[charlie b]

The article 500 series is not my best friend. So I need help.

Outdoor motor fuel pumping station. Huge underground tank. No nearby buildings. Tanker truck pulls next to station and fills up with flexible hose, then leaves to deliver the fuel to some other location. My read is that we have Class I, Div 2 from ground level to 18" above ground level, and to a distance of 20 feet from the dispensing pump. Outside the 20 foot circle is unclassified. Inside the 20 foot circle but higher than 18 inches is also unclassified. My project does not involve the underground tank, and there are no pits nearby, so there is no Class I Div 1 involved. Do I have that right?

How this matters to my project is that we are installing a new branch circuit panel to feed the pumps and auxiliaries. I believe that if it is mounted more than 18 inches off the ground, then it need only be rated for its outdoor location, and not also be rated for a Class I area.

 

[Fulthrotl]

The article 500 series is not my best friend. So I need help.

Outdoor motor fuel pumping station. Huge underground tank. No nearby buildings. Tanker truck pulls next to station and fills up with flexible hose, then leaves to deliver the fuel to some other location. My read is that we have Class I, Div 2 from ground level to 18" above ground level, and to a distance of 20 feet from the dispensing pump. Outside the 20 foot circle is unclassified. Inside the 20 foot circle but higher than 18 inches is also unclassified. My project does not involve the underground tank, and there are no pits nearby, so there is no Class I Div 1 involved. Do I have that right?

How this matters to my project is that we are installing a new branch circuit panel to feed the pumps and auxiliaries. I believe that if it is mounted more than 18 inches off the ground, then it need only be rated for its outdoor location, and not also be rated for a Class I area.

so you are right *above* the classified location.... i've never seen a situation like this, but you will have
conduits exiting the bottom of the panel, going thru the classified location, yes? i believe that conduits
going thru a classified area are subject to the classification, even if the equipment they serve is not
located within the classification. you'd not want fumes migrating to a source of ignition thru the conduit.

were that true, and there were no threaded fittings within the classification, and the first threaded
fitting above 18" was a seal off, common sense would say it was acceptable.

 

[Smart $]

The article 500 series is not my best friend. So I need help.

Outdoor motor fuel pumping station. Huge underground tank. No nearby buildings. Tanker truck pulls next to station and fills up with flexible hose, then leaves to deliver the fuel to some other location. My read is that we have Class I, Div 2 from ground level to 18" above ground level, and to a distance of 20 feet from the dispensing pump. Outside the 20 foot circle is unclassified. Inside the 20 foot circle but higher than 18 inches is also unclassified. My project does not involve the underground tank, and there are no pits nearby, so there is no Class I Div 1 involved. Do I have that right?

How this matters to my project is that we are installing a new branch circuit panel to feed the pumps and auxiliaries. I believe that if it is mounted more than 18 inches off the ground, then it need only be rated for its outdoor location, and not also be rated for a Class I area.

You didn't state the distance relationship of the panel and conduits to the dispensing device. You are correct that the CID2 location is 18" above grade and extends 20' horizontally in all direction from dispenser enclosure... but its also CID2 within 18" of dispenser enclosure or thatportion of dispenser enclosure containing liquid handling components, extending horizontally in all directions and down to grade level... which can be more than 18" above grade.

 

[rbalex]

There are some additional considerations in Section 514.7 for wiring/equipment above classified locations. It probably won't affect you but you should be aware of it. Also note this is not a general requirement, but affects various installations under Articles 511 to 516.