non-utility pad mounted transformers - clearance requirements

[mshields]

I have a couple of pad mounted transformers (1500kVA) on a project. They were pre-purchased some time ago but are not yet installed. The area in which they are to be installed is suddenly more congested than was the original plan and I?m being asked to shoe horn these into a smaller place than I?d prefer.

To my knowledge, the only code requirement is for the work clearance in front of the units. I know that for ordinary dry types, UL requires 6 inches around the unit. Does that apply to Pad mounted transformers as well (don?t worry there will be more than that ? I?m just trying to determine requirements here). Is there a greater requirement for transformers over a certain KVA?

In general what is the minimum space required or recommended on the sides and to the rear of a pad mounted transformer?

Thanks,

Mike

 

[ohmhead]

I have a couple of pad mounted transformers (1500kVA) on a project. They were pre-purchased some time ago but are not yet installed. The area in which they are to be installed is suddenly more congested than was the original plan and I?m being asked to shoe horn these into a smaller place than I?d prefer.

To my knowledge, the only code requirement is for the work clearance in front of the units. I know that for ordinary dry types, UL requires 6 inches around the unit. Does that apply to Pad mounted transformers as well (don?t worry there will be more than that ? I?m just trying to determine requirements here). Is there a greater requirement for transformers over a certain KVA?

In general what is the minimum space required or recommended on the sides and to the rear of a pad mounted transformer?

Thanks,

Mike

Most transformers come with a factory install book inside look at the install clearance sheet . But you should have that before you pour your pad from your supplier !

But i have installed lots of 1000 kva and up on projects 480 /208v Ge and square D and the instructions call out 6 inches back and sides also there is a above space min its included with the specs from factory its best to ask who ever you purchased the transformers from we always exceed this rule to give air flow if its in a tight space .

Check your Nec rules on fire rated walls above a certain KVA ! And if its a underground conduit install check the install meaning cut sheets of your conduit layout as there,s cross beams in large transformers that size and conduit layout is most important . meaning conduit entrance is most important and the window layout must be correct !

Just a bit of advice take care .