LPG Portable container dispensing at gas station Q’s

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tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Greetings all I got a propane tank filler that seems to have had the conduit yanked up.
This is an above ground skid with a tank and a filler mounted on it, the kind a propane company just drop's off and leases a gas station.
The propane company wants the motor converted to 240V from 120 necessitating pulling out the white wire, possibly up-sizing the conductors, re-doing the seal-off's
I have never herd of re-using seal off's but the question came up, is this ever done on a re-pull is there any code / listing issues with it?

poking around the site is leading me to look at a few issues:

I thought there was a 18” depth requirement for conduit under a Class I Division 1 location but I am not finding it in the code.
300.5 column 2 states 6” to top of conduit for rigid is that all that's needed?

The dispenser 'enclosure' is about 4 X 4 X 2 FT grate cage on the front of the skid.
As per 514.3(B)(2):
18” out in all directions from the ‘dispenser enclosure’ and 4FT above ground is Class I Div 1 location Got it motor complies, have seal off's.
Class I Div 2 is 18” above ground and a sphere around it and extends 20’ around the filler?
Whoah
If so it looks like there is a sign disconnect switch in my class I div 2 area.

514.11 required disconnect. The code talks about ‘Attended self service ’ And unattended self-service’ (what about full service ?)
There is an emergency “off” switch about 80 feet away that appears to power a normally closed contactor to open **during** an emergency.
Is there any code other or best practice on these emergency disconnects ? I would think they would be NC and would be wired to a key re-settable button like an e-stop?

Last question should this pump also be tied into the main emergency disconnect for the gas pumps on the building?
It appears it might be.
Its pretty far from the building across a parking lot.
Thanks in advance.
[EDIT for spelling]
 

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Cow

Senior Member
Location
Eastern Oregon
Occupation
Electrician
We've reused sealoffs as long as we're able to knock all the old chunks out. I don't see why it'd be a problem.

As to your other questions, we do propane and explosion proof work but it's not all the time. I usually have to refresh myself with art 500 before I start a project, so I'll let someone else comment on those questions of yours.
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
We've reused sealoffs as long as we're able to knock all the old chunks out. I don't see why it'd be a problem.

As to your other questions, we do propane and explosion proof work but it's not all the time. I usually have to refresh myself with art 500 before I start a project, so I'll let someone else comment on those questions of yours.

Thanks for the reply. Thats good to here.
I think 514.8 covers it with the reference to 300.5
I might just use a 2 pole motor rated switch for the emergency disconnect as its a 20A circuit.
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
1
 

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Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
IIRC from a CE class, sealsare not to be reused. Could be the guy that was giving the class sold those seals so take that into consideration.

514.8 exception No. 2, gives some depth consideration when using PVC.

The method of resetting the emergency disconnect could very well be just turning the disconnect back on. 514.11(A) ."...approved by the authority having jurisdiction."
I would be inclined to include it with the rest of the fuel pumps, if that disconnect meets the 20'/100' min/max. You could have more than one..
 

kwired

Electron manager
Location
NE Nebraska
Is it even worth the time/effort to remove the sealing compound vs cost of a new fitting? Especially for 1/2 and 3/4 inch sizes?
 

Cow

Senior Member
Location
Eastern Oregon
Occupation
Electrician
Is it even worth the time/effort to remove the sealing compound vs cost of a new fitting? Especially for 1/2 and 3/4 inch sizes?

If you take a look at the photo he posted, I would think it's worth a try. It would beat trying to lift off a gutter full of conduits and possibly dealing with existing wiring running through the gutter that may stay, just to make room to replace a sealoff.

If the sealoff was at the end of a stick of conduit by itself, and didn't take more than a few turns from some channellocks to get it off, then that's a different story.
 

kwired

Electron manager
Location
NE Nebraska
If you take a look at the photo he posted, I would think it's worth a try. It would beat trying to lift off a gutter full of conduits and possibly dealing with existing wiring running through the gutter that may stay, just to make room to replace a sealoff.

If the sealoff was at the end of a stick of conduit by itself, and didn't take more than a few turns from some channellocks to get it off, then that's a different story.

Point taken for those seal fittings that are right up to the gutter. Had there been a few inches of nipple between seals and gutter (we always did this, made it easier to pour the seals) all you need to do is cut that nipple with reciprocating saw to get it apart. Assembling the replacement might be a little tricky but is do-able. Some "running thread" on the gutter end will allow you to thread the locknut on far enough to thread the nipple into the seal fitting then back off that locknut to match up to the gutter. One probably adds a little extra thread even when assembling such a thing the first time to allow for minor adjustments where necessary.
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
IIRC from a CE class, sealsare not to be reused. Could be the guy that was giving the class sold those seals so take that into consideration.

514.8 exception No. 2, gives some depth consideration when using PVC.

The method of resetting the emergency disconnect could very well be just turning the disconnect back on. 514.11(A) ."...approved by the authority having jurisdiction."
I would be inclined to include it with the rest of the fuel pumps, if that disconnect meets the 20'/100' min/max. You could have more than one..

I have a similar project for LPG powered busses.
The "...approved by the authority having jurisdiction." means a remote trip CB. That from a morning phone conversation with my AHJ.
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
1
 

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kwired

Electron manager
Location
NE Nebraska
Oh my, the screws holding the ground bus aren't green, you have two whites under one screw. :blink: Have fun with that Clustered Find.

They don't need to be. Only a main bonding jumper that is solely accomplished with a single screw needs to be green. That is usually only limited to a green screw through a hole in the otherwise isolated grounded conductor bus method of bonding.
 

kwired

Electron manager
Location
NE Nebraska
Turns out the feed to the propane pump is the dog leg EMT conduit to the bell box on the far-right its seal off was long gone or non existent.

It doesn't require a seal off at that location. It likely does require one wherever it emerges from below ground or of it never goes below ground then at the boundary of the classified location.
 
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
They don't need to be. Only a main bonding jumper that is solely accomplished with a single screw needs to be green. That is usually only limited to a green screw through a hole in the otherwise isolated grounded conductor bus method of bonding.

Geez, I was not serious at all...he has so much else to deal with.

Is the eyeroll thingy:roll: the best we have for sarcasm?
 
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