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Class 1, Division 2 receptacles??? 2

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CTSpark

Electrical
Feb 1, 2008
1
I am currently on a project which is an Electric Golf Cart Charging Building. The area has been designated as a Class 1, Division 2, Group B location. The receptacles for the chargers are ceiling mount (12' AFF) Nema 5-15R (regular receptacles). Would these receptacles be acceptable for this location?
 
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Battery charging can emit hydrogen gas, which will rise to the ceiling. I think the receptacles have to be rated for the Class I Div 2 Group B classification.
 
If the ventilation system is designed properly it would not typically be considered a hazardous location by U.S. fire codes.
 
I think the bigger issue than the receptacle NEMA configuration, is to consider the rating of the gang box used to mount the receptalce + the conduit/fittings, and sealing requirements.

I'm not positive, but I "think" the NEMA 5-15 receptacle is fine (although I would suggest twist lock type receptacles 12' AFF), but you need to insure the conduits are sealed properly between hazardoud/non-hazardous areas and any j-boxes/faceplates are rated for hazardous areas.
 
If the area is designated Class I, Division 2, Group B then you must comply with the designation. It is true that according to 480.9 (that is 2002 NEC, I am out of my office today and don't have the latest) that if provisions are made for adequate ventilation then the area does not need to be classified. 480.9 refers to stationary storage batteries but you can infer this requirement to mobile equipment.

I have seen many forklift charging installations and none of the area is wired as if it is classified however these areas tend to have permanently open areas from which the gas will vent. I once did a golf cart charging system where the golf carts were charged underground, underneath the pro (golf) shop. There was no direct way to vent upwards so I installed mechanical ventilation with an airflow switch. Lack of airflow would shunt trip the charging equipment. It had typical time delays both for startup and shut down. You could also install a hydrogen combustible gas detector.

If any part of the installation would be considered a classified location it would seem like the ceiling would be since that is where the hydrogen would collect.
 
Where are you going to get the Div 2 chargers?
 
It sounds to me as though the architect may have designed the structure without this issue in mind, then the building inspector is just reacting to what he sees on the drawings. It may be worthwhile to discuss this from that angle rather than try to find equipment capable of being used in a classified area. There is a lot more to it than just picking out the right parts, i.e. personnel safety / training, access and egress, hazmat protection etc. etc. Solve the problem from the building design end as others have said.
 
As discussed above this will be dependent upon the ventilation provided and the quantity/type of batteries present. The local buildings codes, NFPA 70 (NEC) or API RP 500 can provide guidance.

Services provided include: Fire Protection Engineering, Emergency Response Planning, Fire Investigation and Process Safety Management.
 
In my areas (Cl 1, Div 2 Gr D) the receptacles are std duplex, with the circuit interlocked with the vent controllers. Less than full ventillation, no power to the receptacles. We have combustible gas detectors as well, interlocked to start ventillation and sound alarm on high concentrations.

I assume in CTSparks case, as in mine, the chargers are in another area.
 
I have found interpretation of codes pertaining to battery charging varies from one jurisdiction to another in the U.S. It is usually best to ask so you don't have to make changes later.
 
rovineye -- if you assume that the chargers are in another (nonclassified?) area, then why wouldn't you also put the charger receptacles in that same other area to avoid the problem altogether? In the very first post above the OP indicates that these receptacles serve the chargers.
 
rovineye -- your use of "std duplex" receptacles in a Cl 1, Div 2 Gr D location seems to be a violation of the NEC 501.145 requirement that "Receptacles...Divisions 1 and 2 ... shall be identified for the location".
 
A battery room/system designed and installed consistent with Article 480 does not need electrical area classification. In fact, it essentially requires that the installation must not require classification. See Section 480.9(A)
 
peebee,
A little confusion here. First, this is shipboard, so NEC doesn't apply.

After re-reading, you are right, OPs receptacles are for the charger. At first read I was thinking it is the battery connection receptacle. I am too accustomed to hard wired chagers and battery banks.

My space with the permanent battery bank doesn't have any receptacles. The spaces with the receptacles are very large cargo holds, where non-commercial vehicles are loaded and stored, with fuel in their tanks. When the hold is environmentally sealed up,it is treated as class 1 div 2 group D, due to possible fuel leaks and vented tank caps. When all our vent systems are turned on (a couple thousand kW), it isn't classified. So if the crew needs to work on the vehicles,and needs a receptacle, they can fire up all the fans to energize the receptacles. We did need to work with Regulatory Bodies to get approval. It was difficult to get that approval, but I understand may not even be possible in NEC etc world.
 
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