480V, 208V, 240V Current Limiting Reactor

[Mr. Pickle]

Hello All:

I am wondering if anyone has a manufacturer or product recommendation for a packaged current limiting reactor for building applications. I am wondering if there is a practical and reasonably priced packaged unit which is available to limit the available short circuit current in feeder circuits (208,240,480, 3phase).

For those of you whom like more information. In building applications where one would be feeding a Roof Top Unit. Say the roof top unit is rated 208V, 3phase with a SCCR of 5K, however the available short circuit current is 11K. Yes, the roof top manufacturer may be able to provide a unit with a higher SCCR rating, but that is not the question. Question I have is does anyone know of a packaged CLR, which could be installed in the circuit to lower the KAIC in the circuit?

Also I know a transformer is a form of reactor, but again not what I had in mind. Looking for a CLR on the market for such applications, if there is even such a thing.

 

[winnie]

I don't think you would _want_ to do this, because you would be introducing voltage drop that would reduce your system performance. But with that said, what you are describing sounds just like a 'line reactor' sometimes used for VFDs to add impedance on the supply side. These are often used with line regenerative VFDs.

Whoops, I guess except for the 'packaged' part.

As you note, a transformer introduces impedance in the line, but I presume you want to avoid using a conventional transformer because it would need to 'transform' the full kVA being delivered to the load. I am guessing that you want something packaged like a dry type transformer, but sized to as a reactor which is much smaller.

It looks like 'Grainger' carries them: https://www.grainger.com/category/m...rs-and-soft-starts/drive-reactors-and-filters

 

[ron]

Most transformer manufacturers will make a packaged iron core reactor for you such as https://www.hammondpowersolutions.com/en/products/categories/custom-products

It is almost always better to get the right HVAC starter equipment to save footprint, installation cost and potential voltage drop issues.

 

[Jraef]

Current Limiting Reactor | L/C Magnetics

L/C Magnetics Is A Manufacturer Of Current Limiting Reactors (Clr). Current-Limiting Reactors Are Series Inductors Intended To Reduce The Short Circuit Currents Passing Thru The Circuit Breaker In The Power System. A Higher Voltage Is Developed Across The Clr When The Current Thru The Clr Increases.

www.lcmagnetics.com

But it’s not as simple as you might think, and as said, there are consequences. You are trying to solve a problem that is much more simply addressed by telling users to have someone determine their available fault current and insist that the suppliers comply with a suitable SCCR. Otherwise what you are trying to do is engineer the site, rather than have the suppliers properly engineer their equipment. It is NOT that difficult to get a higher SCCR, not in the least. People who default to 5kA are just cheap and lazy.