514.11(A) Does a Propane pump get tied into gas station e-stop?

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tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Greetings all I am reviewing NEC 514 for some upcoming projects that involve adding a propane filler to a gas station.
This is typically what you refill a RV propane tank, 5 gal BBQ tank, or the rare propane powered vehicle (apparently I am told they exist never seen one)
Its one facility, with say 2 hazardous locations two gas islands now a proposed 3rd (propane filler). The locations dont overlap.

Does the propane filler location need to be tied into the e-stop for the other two?
Or can each have its own e-stop?
From what I have seen in the feild I think the islands (haz locations) each have their own, that are independent.
Reviewing 514.11(A) Circuit Disconnects sentence 3 is making me think current NEC wont allow that and they all get tied together:

Emergency shutoff devices or electrical disconnects shall disconnect power to all dispensing devices;
The use of the word All seems like it would include the entire facility.
to all remote pumps serving the dispensing devices;
to all associated power, control, and signal circuits;

and to all other electrical equipment in the hazardous (classified) locations surrounding the fuel dispensing devices.
When more than one emergency shutoff device or electrical disconnect is provided, all devices shall be interconnected.

locations plural instead of location make me think all the pumps at a site need to be on one e-stop.

Say you had two large gas filling islands on opposite sides of a convenience store and a propane filler a decent distance away from them.
Does the estop typically serve the entire 'Facility'
Thanks in advance
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
The only gas stations I’ve seen with propane fill, was at large truck stops. The rest were farm supplies or hardwares. Never noticed if it was tied to the gas e-stops. My cousin has an old Dodge utility truck that ran on propane. It was a retired telephone company truck.
 

rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
Remember, I’m offering this answer as a personal opinion.

Section 514.11 should be interpreted in light of the Scope of the Article. [Section 511.1] In this case, the propane pump is probably not part of a motor fuel dispensing system; however, with respect to Section 514.11, it is part of the facility. Reasonable caution would indicate that Section 514.11 would therefore apply.

The opening sentence of Section 514.11(A) would indicate that it applies to systems (plural) rather than each isolated system. Again, reasonable caution would indicate that each system with the potential of affecting other systems should be considered in the emergency shut-down system. Personally, I would consider hazardous (classified) locations that are connected or contiguous have the potential of affecting each other.

I believe this opinion to be consistent with the overall intent of Section 514.11.
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Thanks all for the replies, I made and inquiry to the AHJ.
Remember, I’m offering this answer as a personal opinion.

Section 514.11 should be interpreted in light of the Scope of the Article. [Section 511.1] In this case, the propane pump is probably not part of a motor fuel dispensing system; however, with respect to Section 514.11, it is part of the facility. Reasonable caution would indicate that Section 514.11 would therefore apply.

The opening sentence of Section 514.11(A) would indicate that it applies to systems (plural) rather than each isolated system. Again, reasonable caution would indicate that each system with the potential of affecting other systems should be considered in the emergency shut-down system. Personally, I would consider hazardous (classified) locations that are connected or contiguous have the potential of affecting each other.
Thanks rbalex, so if you were designing a large gas station with two independent fuel islands say 200' apart would you have one interconnected set of e-stop's for the whole facility?
When I have had trouble with say a bad pump and it triggeers the e-stop I believe it only disables one island. But that could also be some different circui logic foor pump trouble. ( EDIT and they are say 10-20 year old stations now)
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
Thanks all for the replies, I made and inquiry to the AHJ.

Thanks rbalex, so if you were designing a large gas station with two independent fuel islands say 200' apart would you have one interconnected set of e-stop's for the whole facility?
When I have had trouble with say a bad pump and it triggeers the e-stop I believe it only disables one island. But that could also be some different circui logic foor pump trouble. ( EDIT and they are say 10-20 year old stations now)
The e-stops are not controlled by the pumps, so that shouldn’t be an issue.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
Usually the cashier has one behind the counter along with ones at the doors too, so I don’t see that as being a big issue.

Most cashiers in those places around here don't even know what day it is and wouldn't tell you if you asked them. I hit the e-stop once because the nozzle wouldn't shut off and the attendant said I didn't know how to pump gas.

I believe legally the e-stops have to be located in accessible locations near the devices they control.

-Hal
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Interesting little update on this, turned out it was going to be quite involved at one of the sites to tie in the propane filler e-stop to the existing e-stops, so this issue got sent back to me to be looked at again, then sent to corporate, then back to me, the inspector, and on up the chain to the chief inspector for the state, and drumroll ...
it appears this does not apply to an entire facility it applies to ‘Fuel dispensing systems’ .
One of the factors is 514.11’s title ‘Circuit Disconnects’ rather than something like 'Facility Disconnects'.

The NEC does define a ‘Motor Fuel Dispensing Facility’ now (2020) in article 100
The term ‘Facility’ is not included in 514.11
The NEC, and NFPA 30A do not define a ‘Fuel dispensing system’ however all involved agreed a reasonable definition would include 'all the components of a single fuel pump including of all associated power, control, and signal circuits and the remote pump serving the single dispensing device'.
A typical ‘gas island’ is a Hazardous (classified) location that consists of one or more ‘Fuel dispensing systemsthat are contiguous and thus do have the potential of affecting each other.
A gas island then meets the definition of ‘Motor Fuel Dispensing Facility’ as its a portion of a property.

There can be several independent portions of one large property like a truck stop, 514.11 states locations surrounding, in order to surround means to extend on all sides of simultaneously or encircle, so a remote island or propane filler would not be considered as surrounding the fuel dispensing devices, rather its a separate portion of the property or a separate ‘Motor Fuel Dispensing Facility’ if you will , per the NEC definition.
More clarity from CMP 14 would be best, especially with their avoidance of the defined term ‘Motor Fuel Dispensing Facility’ in article 514.11
and as always such matters are ultimately up to your AJH
 
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