Keep It Simple Simon
Member
- Location
- California
- Occupation
- Plant Engineer
First post on this forum. I spent over 20 years in the industry as an industrial, then commercial, then residential and off grid systems electrician, however, have spent the last 10 years cosplaying as a plant engineer for a small manufacturing company, so some of my knowledge may have become dated. I do have a 2014 copy of the NEC which I do use to consult for questions I do not know the answers to already. On this topic, I need some help.
Our business is preparing to move to a new location where the in-suite primary 480 volt 3 phase sub panel (along with a series of poorly laid out transformers and 208 volt sub panels) in mounted to a wall where we need to install pallet racking. I plan to consolidate and relocate the transformers and low voltage panels, but relocating the primary panel will be cost prohibitive unless absolutely necessary. Before I get too far down the rabbit hole laying out new locations and racking plans, I need some help determining relevant clearances we will need to maintain.
I am aware of the 30" horizontal working space, and the 36" depth rules for sub panels, but I have not identified a required clearance from the side of the sub panel to the nearest frame of any pallet racking. Our rack guy says we need 36" of clear space from the side of any panels or transformers to the nearest rack structure, but he admits he does not know NEC.
My own research on the topic shows that I need to provide a cross aisle and down aisle clearance of the rack structure in proportion to the highest point a load will be placed upon, but this does not differentiate between structure or utility devices. I know that I could install a sub panel with its side up against a wall as long as there is 30" of side to side working space, 36" of depth clearance, and if the ability to open the door of the sub panel 90 degrees or more is maintained.
I also know that dry type transformers only require manufacturer specific clearances for ventilation.
My questions to this forum are:
Is our rack guy correct?
Do I need to allow for 36" of rack structure to side of sub panel or side of transformer clearance?
Appreciate the advice. Stay safe.
Our business is preparing to move to a new location where the in-suite primary 480 volt 3 phase sub panel (along with a series of poorly laid out transformers and 208 volt sub panels) in mounted to a wall where we need to install pallet racking. I plan to consolidate and relocate the transformers and low voltage panels, but relocating the primary panel will be cost prohibitive unless absolutely necessary. Before I get too far down the rabbit hole laying out new locations and racking plans, I need some help determining relevant clearances we will need to maintain.
I am aware of the 30" horizontal working space, and the 36" depth rules for sub panels, but I have not identified a required clearance from the side of the sub panel to the nearest frame of any pallet racking. Our rack guy says we need 36" of clear space from the side of any panels or transformers to the nearest rack structure, but he admits he does not know NEC.
My own research on the topic shows that I need to provide a cross aisle and down aisle clearance of the rack structure in proportion to the highest point a load will be placed upon, but this does not differentiate between structure or utility devices. I know that I could install a sub panel with its side up against a wall as long as there is 30" of side to side working space, 36" of depth clearance, and if the ability to open the door of the sub panel 90 degrees or more is maintained.
I also know that dry type transformers only require manufacturer specific clearances for ventilation.
My questions to this forum are:
Is our rack guy correct?
Do I need to allow for 36" of rack structure to side of sub panel or side of transformer clearance?
Appreciate the advice. Stay safe.
