Does Automatic Transfer Switch require 6ft clearance above it per 110.26(F)(1)(a)?

[SP1459]

NEC 110.26(F) - Dedicated Equipment Space. All Switchboards, panelboards, distribution boards and MCC shall be located in dedicated spaces and protect from damages. And NEC 110.26(F)(1)(a) Dedicated Electrical Space requires 6 ft above the equipment or structural ceiling shall be dedicated to the electrical installation. No piping, ducts etc allows in this 6 ft zone.

Is 1600A ATS Floor Mounted (6 ft high) considered as either Switchboards, panelboards, distribution boards and MCC that requires 6 ft clearance above? Can HVAC duct be running at 3 ft above ATS?

 

[infinity]

If it's not on the list then the 6' rule does not apply.

 

[ron]

Since there is no NEC Article, UL listing or definition that identifies a distribution board, an ATS might be considered that.

 

[infinity]

Since there is no NEC Article, UL listing or definition that identifies a distribution board, an ATS might be considered that.

Sorry Ron but that's a stretch. As stated in its name it's a switch.

 

[m sleem]

Sorry Ron but that's a stretch. As stated in its name it's a switch.

IMHO, it has a relation with number of feeders connected.

 

[tom baker]

IMHO, it has a relation with number of feeders connected.

What do feeders have to do with the working space rule? The rule lists which equipment is included.

 

[ron]

What do feeders have to do with the working space rule? The rule lists which equipment is included.

What equipment is under the definition of distribution board?

 

[ggunn]

Sorry Ron but that's a stretch. As stated in its name it's a switch.

Most of the time at residences it's a main service disconnect and subject to the same rules.

 

[charlie b]

What do feeders have to do with the working space rule?

It's not "working space." It's "dedicated equipment space." My opinion, and it is no more than that, is that this rule lists only four types of equipment because they are the only items that have the possibility of having additional conduits installed in the future. The rule provides space for that future installation. Once an ATS, or a transformer, or a disconnect switch, or other item is first installed, there will never be a future need for adding more conduits.

 

[augie47]

Just another opinion, but I agree 100% with charlie b on his opinion and logic.

 

[wwhitney]

Just to stir the pot a little, regardless of intention, does a 1600A floor mounted ATS fit the definition of a switchboard?

Switchboard. A large single panel, frame, or assembly of panels on which are mounted on the face, back, or both, switches, overcurrent and other protective devices, buses, and usually instruments. These assemblies are generally accessible from the rear as well as from the front and are not intended to be installed in cabinets.

Cheers, Wayne

 

[pv_n00b]

It's a stand-alone two-position A-B switch so I would not consider it to fall under that section, but your AHJ may argue that. If the transfer switch was mounted in a switchboard section as part of a larger collection of switchboard sections that would be different.

 

[ggunn]

It's not "working space." It's "dedicated equipment space." My opinion, and it is no more than that, is that this rule lists only four types of equipment because they are the only items that have the possibility of having additional conduits installed in the future. The rule provides space for that future installation. Once an ATS, or a transformer, or a disconnect switch, or other item is first installed, there will never be a future need for adding more conduits.

When we connect a PV system to the line side of an ATS or other service disconnect, we add conduit to it.

 

[jim dungar]

.... the only items that have the possibility of having additional conduits installed in the future. The rule provides space for that future installation.

Charlie, I would agree with yu more if you used the word 'likelihood' instead of ' possibility'.
Just about any modification might be possible, however most of them would rarely occur.

 

[charlie b]

When we connect a PV system to the line side of an ATS or other service disconnect, we add conduit to it.

That is a rare enough event not to warrant inclusion in the list of items requiring dedicated equipment space.

 

[ggunn]

That is a rare enough event not to warrant inclusion in the list of items requiring dedicated equipment space.

I agree with Jim - likelihood instead of possibility. It's a common occurrence for me.