Suspending transformers

[mparkstexas]

We are looking at suspending 150 kVA, dry type transformers from the structure inside of a manufacturering facility (yes, structural is in on it).

I am using 450.21(b)(ex.1). But was wondering if we needed 12' vertical clearance on top and bottom, for a total of 24' + transformer height?

Any thoughts? Anyone ever seen this done before?

 

[charlie b]

I often design rooms to have suspended transformers. The room is generally of a 1 hour construction, so the 12 foot rule doesn't come into play. Also, if there is a fire resitant barrier (i.e., in the floor and ceiling materials), you don't need the vertical clearance. Finally, there is Exception 2 to consider. Most transformers I have seen in my projects would satisfy Exception 2.

 

[Corey Zachel]

i would say you need the vertical clearance from the combustible material and only 110.26 work clearance above and in front of. you threaded rod and unistrut trapeze hanging it?

 

[iwire]

i would say you need the vertical clearance from the combustible material and only 110.26 work clearance above and in front of. you threaded rod and unistrut trapeze hanging it?

Does a transformer require servicing while energized?

 

[Corey Zachel]

Does a transformer require servicing while energized?

not when you're safety first. he said a manufacturing facility though so i assumed safety by design because maintenance staff generally do what they can without de-energizing equipment which can stop process and get the plant manager a little hot due to production loss.

 

[jeremysterling]

Does a transformer require servicing while energized?

I've had the AHJ tell me it does.