Re: Electronic Box Shielding ?

Mariss:

Thanks for responding.

At 01:17 AM 11/28/00 +0000, you wrote:

>1) Use steel. It is a magnetic as well as electric field shield.

OK. Doesn't seem harder to use steel and if it'll help....

>2) If you can, have it contain the motor power supply as well.

Done.

>3) Use an RFI line filter on the 115VAC where it enters the box.

OK, but what's an RFI line filter? Is this like an RC filter
set at somewhere above 60Hz or some more sophisticated
circuit? Are these purchasable and can you give a source
or two? :-)

>4) Use a 5-conductor shielded cable / motor. The 5th conductor goes
>from motor case to ground inside the box.

This would be a fifth wire in addition to shielding? Wouldn't this
form a ground loop, ground/motor case/fifth wire/ground?

>5) Ground the shield at the box end. Do not connect the far end.

Check.

>6) Establish a "holy point" ground inside the box. All internal
>ground wires go to this single point. Everything that needs a ground
>wire gets a seperate, individual wire from this point.

OK. Someone previously suggested the (-) terminal of the
power supply capacitor. Is this good? Should this point in turn
be taken to an earth ground?

>7) Keep inputs (STEP, DIR) apart from motor output leads.

Check.

>8) Shield input cables the same way as (5).

I was planning to use twisted shielded pairs for wiring.
Then use the twisted pair for signal and return. Is this
appropriate and/or important?

>9) Do not run limit switch and other aux lines thru the box.

Gotcha.

>10) Ground the box to earth ground.

Cool.

>Follow these simple rules and you will prosper.

'bout time I got some of that "Prosper".

>Mariss
>Geckodrive Inc.

Thank you greatly, it is already a big help. And also thanks
for your Geckodrive site, it has answered a few other questions
for me. :-)

Hugh Currin
Klamath Falls, OR