On Oct 16, 6:59*pm, Jeffrey Angus wrote:
On 10/16/2011 8:42 PM, William Sommerwerck wrote:

Do you have good reason to believe that AWG 30 is the proper
gauge, and that your calculations are correct?

http://www.pronine.ca/multind.htm

Yields both the correct inductance and DC resistance with #30
AWG for the assumptions I've made for the physical size of the
coil bobbin.

If so, then buy the wire and do it. If it doesn't work, you're
out only $20 and the time it took to wind the coil.

I don't know enough about solenoids to properly judge your
calculations. But I don't see anything obviously wrong.

And that's why I thought I'd ask here. I was hoping to find
someone that _is_ familiar enough to at least tell me, "Yeah,
you seem to be heading in the right direction."


You didn't say this solenoid was part of a transfer switch. This
raises the stakes substantially. Transfer switches are used to switch
the mains supply to a generator when mains power is interrupted. They
serve two main purposes: to keep critical equipment functioning when
mains power is interrupted, and to deenergize the power line so that
workers can assume it is deenergized when they work on it.

Now, the transfer switch was tested to meet specifications with the
designed solenoid installed. Knowing nothing of the design or
construction of the component, you propose to roll your own and stick
it in.

Which would be fine, if no one's life depended on its working. And if
the vendor would stand behind your handicraft.

I don't think Asco could reasonably foresee that someone would use a
program that gives the number of turns for an air-core inductor to
design a part for a life-safety application.