# Re: DC charging reactor

```Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>

> The steel density is a fixed value with a value for magnetic permeability.
> This is usually dependent on the silicon content of the iron you are using
> (this data from mfgr).  You need to see the actual hysteresis curve for the
> steel you have.

> Your core would be the 4.5 x 6.5 value = 30 sq. in.
???

Respectfully, the description:
(extracted)
>>It measures 6.5 inches long by 4.5 inches wide. The ring
>> width is about 1 inch and the laminiations are 1 inch
>> thick.  So it's as if I took a 1"x1" iron bar and bent
>>it 90 degrees four times forming a 4.5 x 6.5 rectangle.
sounds like:

1 square inch (roughly....)

> There is a good section in the ARRL Radio Amateur's Handbook on these
> hysteresis curve factors.
Good point.

=========================================================

>>Hmmm. I'm still having trouble picturing this in my head, the part
>>slicing through the core. There are about 6 dimensional ways of doing this
>>and I'm not sure which way you mean... If I throw out an example can you
>>elaborate?

>>    For my reactor I cut a MOT core into its 'E' and 'I' sections. I sawed
>>the middle leg out of the E, turning it into a 'C'. I split the C into 2
>>piles of laminations and stuck these end to end forming a rectangular
>> ring.

>>It measures 6.5 inches long by 4.5 inches wide. The ring width is about 1
>>inch and the laminiations are 1 inch thick. So it's as if I took a 1"x1"
>>iron bar and bent it 90 degrees four times forming a 4.5 x 6.5 rectangle.
>>There is a winding on each of the 6.5" sections.
>>So is the 'cross sectional area' simply 6.5 x 4.5? Surely the
>> thickness of the laminations (read overall iron mass) has to

>> figure into this somewhere. Help, I'm geometrically challenged

>> and I cant get up ;)
>>
>>    Smoke test says it handles 1400KVA  without saturation...

best
dwp

...the net of a million lies...
Vernor Vinge
There are Many Web Sites which Say Many Things.
-me

```