1000KVA indoor xfmr

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mimo

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gentlemen,
I need a help from and expert here, I have to use a 1000kva, primary voltage 25kv to 480v secondary voltage transformer it used to be outside the building and now the Owner wants it to be indoor, I know know i have to use dry type transformer now otherwise i need to build a vault for it do anybody tell me what are the manufactures for that size dry type transformer?
also what is the difference between oil filled and silicon filled transformer
Thank you for your time
 
amingomaa said:
gentlemen,
I need a help from and expert here, I have to use a 1000kva, primary voltage 25kv to 480v secondary voltage transformer it used to be outside the building and now the Owner wants it to be indoor, I know know i have to use dry type transformer now otherwise i need to build a vault for it do anybody tell me what are the manufactures for that size dry type transformer?
also what is the difference between oil filled and silicon filled transformer
Thank you for your time
Click to expand...
check here
http://www.dowcorning.com/content/power/powerfluid/
 
I think silicone is a non-flammable fluid (or maybe its a less-flammable fluid.)

If it's nonflammable, I don't think you necessarily need a vault for an indoor installation.
 
Those are pretty weird specs for a dry type, you might need a special order unit, do you have any more details? Delta/Wye, actual primary voltage??
 
1. Oil filled can be used indoors without having a vault.

2. This type of transformer can be had by many manufacturers. Deal directly with the inside sales guy at your local wholesale house. The 25KV HV side, may increase the lead time and you will need to keep that in mind when planning/scheduling your work.
 
amingomaa said:
gentlemen,
I need a help from and expert here, I have to use a 1000kva, primary voltage 25kv to 480v secondary voltage transformer it used to be outside the building and now the Owner wants it to be indoor,
Click to expand...
Don't forget to order the spare transformer.
 
steve66 said:
kingpb said:
1. Oil filled can be used indoors without having a vault.
Many oil filled transformers do require a vault. 450.26.
Click to expand...

What is your point? Oil filled can be used indoors without having a vault, per 450.23. Yes, "many" do require a vault, but "Many" does not mean all.

From Cooper: "Envirotemp FR3 fluid and 561? Silicone Transformer Liquid are the only two less-flammable fluids with UL listing EOVK. UL EOVK covers less-flammable liquids intended for use in electrical transformers to meet the National Electrical Code (NEC) Section 450-23. Of these, FR3 fluid has the highest flash/fire point, best environmental profile, lowest cost and is miscible with other transformer fluids."

So as not to misinterpret oil versus fluid, envirotemp FR3 is made from edible seed oils
Click to expand...
Click to expand...
 
My point is that the statement you made:

"Oil filled can be used indoors without having a vault."

is incorrect.

It would have been correct if you had qualified it by saying:

"Some oil filled can be used indoors without having a vault."
 
Pay close attention to the type of environment. If you are going to use a dry-type transformer and there is going to be opportunity for impurities to settle on the coils, a cast coil is the way to go or even something a little more exotic might be needed.
 
You are interpreting my statement to mean "all". When in actuality, all was not used or implied, and therefore your interpretation is what is incorrect.

What is implied by my statement is that in accordance with the Code, certain conditions do allow for oil filled transformers to be installed without a vault. Whereas, you implied that in accordance with 450.26, all oil filled transformers do require a vault, because you did not qualify your statement with allowances set forth in 450.23.

Was it really necessary to try and use wordplay to bolster an opinion? What purpose did it serve? Did it make you more right?

If people would stick to the OP question, this forum would be better served.
 
""Oil filled can be used indoors without having a vault."

Thats not incorrect, they can. "Oil transformers used indoors do not require a vault" is incorrect.
 
amingomaa said:
gentlemen,
I need a help from and expert here, I have to use a 1000kva, primary voltage 25kv to 480v secondary voltage transformer it used to be outside the building and now the Owner wants it to be indoor, I know know i have to use dry type transformer now otherwise i need to build a vault for it do anybody tell me what are the manufactures for that size dry type transformer?
also what is the difference between oil filled and silicon filled transformer
Thank you for your time
Click to expand...

Dry type transformer would not need a fire-resistant vault.

Liquid filled transformers installed indoors would need to have a vault, unless the enclosure is equipped with automatic fire supression or the transformer is FM approved and labeled for THAT purpose, meeting the following criteria:

1./ less flammable insulated liquid
2./ avaliable short circuit energy is limited by eitehr external or internal means
3./ pressure relief device is rated to the specified flow rates.

Outdoor instalaltions also require the transformer to be away from combustibles or surrounded by fire-walls.
 
If you have a need for a "liquid filled" transformer you better check the lead times because that may cause you to strongly consider a dry type venilated transformer.
More expensive but the lead time may be 8 weeks.
 
templdl said:
If you have a need for a "liquid filled" transformer you better check the lead times because that may cause you to strongly consider a dry type venilated transformer.
More expensive but the lead time may be 8 weeks.
Click to expand...

Lead times for many liquid filled are up to 6 months now.
 
Why the national electrical code

Why the national electrical code

Why the national electrical code for dwelling units don't apply the continuous and non continuous load to calculate the over load protection device and cable selection calculation, correction factors for temperature



The national electrical code discuses about the motor-compressor, motor-compressor largest load, protective device, and no discussion about air handling units, chillers



the national electrical code discuses the method of calculating the demand load one panel board the question if I have panel (A) and (B), (C), (D), each of them contain lighting , motors and sockets loads and appliances and air conditions how I cane calculate the demand load for the main panel MDB-1 that feed all this panel boards and the main feeder, main circuit breaker and calculate the demand load of panel board MDB that feed the (MDB-1), (MDB-2), (MDB-3), (MDB-4) ,main feeder, main circuit breaker where (MDB-2), (MDB-3), (MDB-4) same as MDB-1 but different in loads not typical and, also calculation transformer load.



The national electrical code discuses the demand loads of central space heating only for optional method for dwelling units what about the general method for dwelling units and the non-dwelling units.
 
faranca77 said:
Why the national electrical code for dwelling units don't apply the continuous and non continuous load to calculate the over load protection device and cable selection calculation, correction factors for temperature

The national electrical code discuses about the motor-compressor, motor-compressor largest load, protective device, and no discussion about air handling units, chillers

the national electrical code discuses the method of calculating the demand load one panel board the question if I have panel (A) and (B), (C), (D), each of them contain lighting , motors and sockets loads and appliances and air conditions how I cane calculate the demand load for the main panel MDB-1 that feed all this panel boards and the main feeder, main circuit breaker and calculate the demand load of panel board MDB that feed the (MDB-1), (MDB-2), (MDB-3), (MDB-4) ,main feeder, main circuit breaker where (MDB-2), (MDB-3), (MDB-4) same as MDB-1 but different in loads not typical and, also calculation transformer load.

The national electrical code discuses the demand loads of central space heating only for optional method for dwelling units what about the general method for dwelling units and the non-dwelling units.
Click to expand...

..and the above relates to the topic in what way?
 
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