panel behind switchboard violation

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hhsting

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Attached sketch shows Panel CP in back of large equipment switchboard more than 1200A and more than six feet wide. They provide double working space and distance from large equipment to nearest edge door is 4 feet satisfying 110.26(c)(3)(2).

The switchboard is front access only. Workspace from panel CP to back of switchboard is 4 feet.

Is their anything in NEC 2017 that says Panel CP cannot be in the back of the large equipment switchboard?

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Take a look at 110.26(A) and let us know how you would apply the working space requirements for both panel CP and the large switchboard. Read 110.26(A)(1)(a) especially carefully when thinking about your large switchboard.
 
d0nut said:
Take a look at 110.26(A) and let us know how you would apply the working space requirements for both panel CP and the large switchboard.
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110.26(A)(1) Panel CP is 208V while gear is 480V so 4 feet.

For switchgear their is no working space dead front 11026(A)(1)(a) front access only

I was more speaking of 110.26(C)(1) for panel CP in the event gear exploded there wont be sufficient egress from Panel CP working space
 
For Panel CP, what is the voltage of your exposed, live parts? That is what determines which row to use in Table 110.26(A)(1).

As with regards to 110.26(C), what space requires the entrance to and egress from?
 
For Panel CP, what is the voltage of your exposed, live parts? That is what determines which row to use in Table 110.26(A)(1).

Response: Panel CP is 208V three phase
Other end gear is 480V three phase


As with regards to 110.26(C), what space requires the entrance to and egress from?

Response: Panel CP space requires egress to and from. Back of gear their is No working space
 
For Panel CP, the fact that the gear in front of it is 480V is immaterial since there is no rear access to the 480V live parts. Panel CP would be Condition 2 in the 0-150V row, requiring 3' of working space.

So, to summarize, Panel CP requires 3' of working space in front of it. The large equipment, since it is front access only, has no working space required behind it. Since there is no required working space behind the large equipment, the requirements of 110.26(C) do not apply to the rear of that equipment. Therefore, the minimum space required between Panel CP and the large equipment is 3'. Since 4' of space was provided, the installation is compliant.
 
hhsting said:
110.26(A)(1) Panel CP is 208V while gear is 480V so 4 feet.

For switchgear their is no working space dead front 11026(A)(1)(a) front access only

I was more speaking of 110.26(C)(1) for panel CP in the event gear exploded there wont be sufficient egress from Panel CP working space
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The code does not require that.
 
d0nut said:
For Panel CP, the fact that the gear in front of it is 480V is immaterial since there is no rear access to the 480V live parts. Panel CP would be Condition 2 in the 0-150V row, requiring 3' of working space.

So, to summarize, Panel CP requires 3' of working space in front of it. The large equipment, since it is front access only, has no working space required behind it. Since there is no required working space behind the large equipment, the requirements of 110.26(C) do not apply to the rear of that equipment. Therefore, the minimum space required between Panel CP and the large equipment is 3'. Since 4' of space was provided, the installation is compliant.
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You mean 110.26(C)(2) which is about large equipment Wont apply but 110.26(C)(1) will apply to Panel CP?
 
hhsting said:
You mean 110.26(C)(2) which is about large equipment Wont apply but 110.26(C)(1) will apply to Panel CP?
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Correct. I was stating that the requirements of 110.26(C) would not apply to the rear of the large equipment with regards to that equipment. Since Panel CP is located to the rear of the equipment, the requirements of 110.26(C)(1) would apply to Panel CP's working space as you have noted.
 
110.26
(a) Dead-Front Assemblies. Working space shall not be required in the back or sides of assemblies, such as dead-front switchboards, switchgear, or motor control centers, where all connections and all renewable or adjustable parts, such as fuses or switches, are accessible from locations other than the back or sides.
 
augie47 said:
110.26
(a) Dead-Front Assemblies. Working space shall not be required in the back or sides of assemblies, such as dead-front switchboards, switchgear, or motor control centers, where all connections and all renewable or adjustable parts, such as fuses or switches, are accessible from locations other than the back or sides.
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Ok got it. But what else is their in the back as I have been saying? Something is in the back wall and behind swgr that requires work space and egress and entrance?
 
Is their anything in NEC 2017 that says Panel CP cannot be in the back of the large equipment switchboard?
hhsting said:
Is their anything in NEC 2017 that says Panel CP cannot be in the back of the large equipment switchboard?
Click to expand...
No !

Question answered by more than one.
 
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