What is the NEC definition of "Immediately Adjacent"?

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Jon456

Senior Member
Location
Colorado
I have two pump motors in a pump house (about 10 feet square). The main power feed to each pump is 3-phase 230VAC via a fusible disconnect panel within the pump house. There is a common controller panel that alternately activates each pump (or both simultaneously if conditions warrant). The power to the controller is fed from a 20A 2-pole breaker in a single-phase subpanel; both the controller and the subpanel are also within the pump house. Inside the controller are two 25A 2-pole breakers (both off the same 20A main controller feed) that normally would supply small pump motors; currently these are unused.

Rather than tap power off each of the motors' main feeds to energize the associated control and starter circuitry, I'd rather take the control/starter power from the controller panel. I was thinking of using the two 25A breakers in the controller panel to feed each of the pump's control circuit. That would mean that each control circuit could be individually shut off at the control panel, or both control circuits could be de-energized by turning off the 20A breaker to the controller at the subpanel.

So now my question...
NEC 430.75 (Disconnection) states regarding motor power and control circuits: "Where separate [disconnecting] devices are used, they shall be located immediately adjacent to each other."

So what exactly does "immediately adjacent" mean? The panels are within sight of each other? The panels are both on the same wall? The panels are within 12" of each other? The panels are touching?

In my case, the main fusible disconnect for Pump #1 is on one wall and the controller for both pumps is on the same wall within 3 feet. The fusible disconnect for Pump #2 is on an adjacent wall within perhaps 4-5 feet of the controller. The fusible disconnect for Pump #2 is also on the same wall as the subpanel (that energizes the controller), within 1 foot of each other. For my application, do the panels qualify as "immediately adjacent"?
 

qcroanoke

Sometimes I don't know if I'm the boxer or the bag
Location
Roanoke, VA.
Occupation
Sorta retired........
adjacent

1. [a] nearest in space or position; immediately adjoining without intervening space ; "had adjacent rooms"; "in the next room"; "the person sitting next to me"; "our rooms were side by side".
 

Jon456

Senior Member
Location
Colorado
adjacent

1. [a] nearest in space or position; immediately adjoining without intervening space ; "had adjacent rooms"; "in the next room"; "the person sitting next to me"; "our rooms were side by side".

That appears to be a dictionary definition. (And if I'm sitting next to a person, there had better be "intervening space" unless that person is someone I'm intimate with!)

In any case, there are many variations in dictionary definitions. For example, from one dictionary:

adjacent (e-j?sent) adjective
1. Close to; lying near: adjacent cities.
2. Next to; adjoining: adjacent garden plots.

"Close to" and "next to" (adjoining) are NOT the same meaning. And even the definition "close to" is relative (compared to other stars, Earth is VERY close to the sun). Thus the word adjacent is ambiguous in a regulatory context unless the regulation actually defines the term as it is to be applied.

So does the NEC actually define the term "adjacent"?
 

charlie b

Moderator
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Location
Lockport, IL
Occupation
Retired Electrical Engineer
So does the NEC actually define the term "adjacent"?
It does not. That leaves it up to the AHJ. Have you had a talk with that person?

FWIW (probably not much), my take is that I would need to be able to touch both panels at the same time. That puts them within 6 feet, but not necessarily on the same wall.
 

Jon456

Senior Member
Location
Colorado
FWIW (probably not much), my take is that I would need to be able to touch both panels at the same time. That puts them within 6 feet, but not necessarily on the same wall.

That does seem to be a practical interpretation. I can touch Pump #1 disconnect and the breaker in the controller panel simultaneously, and I can touch Pump #2 disconnect and the controller breaker in the subpanel simultaneously.
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Retired Electrical Engineer
Pierre, I think he was agreeing with me. Or did you think there was a "not" in his statement? :D
 
Pierre, I think he was agreeing with me. Or did you think there was a "not" in his statement? :D


You are intuitive...


The change in the NEC from adjacent to immediately adjacent has me puzzled.

Why did the CMP decide to change from adjacent to immediately adjacent, without providing more help in deciding what it really means. During their discussions/writings, they must have said something to each other to decide to make the change. Why not provide a measurement???

Your guide of being able to touch them is good for you, but what about the different people out there who have a difference in reach?
Say you have a 6 ft reach and the inspector comes in and only has a 4'-6"
reach? Does this mean the you would have to reinstall it?
 

Jon456

Senior Member
Location
Colorado
Just to be clear... yes, I was agreeing with Charlie. :smile:

Say you have a 6 ft reach and the inspector comes in and only has a 4'-6" reach? Does this mean the you would have to reinstall it?

Perhaps we need an NEC standard for the minimum size of electrical inspectors! :D
 
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