[TowerTalk] Relay lightening protection

[Kipton Moravec]

On Fri, 2009-01-30 at 06:53 -0800, jimlux wrote:
> donovanf at starpower.net wrote:
> > This discussion of relay reliability and switching speed is
> > irrelevant for a relays in a phased array that should never be hot
> > switched.
> 
> The reliability issues in the Tyco ap note aren't tied to whether the 
> contacts are carrying current.
> 

Carrying current IS the whole issue. If they were not carrying current
then it does not matter how fast the contacts close or open.

The goal of the applications note was to minimize the contact arcing,
which increases contact life or reliability. It is described in the
second paragraph of the second column of the first page. 

http://relays.tycoelectronics.com/appnotes/app_pdfs/13c3311.pdf

You do not have arcing if there is no current. So if there is no current
then contact speed is not an issue.


-- 
Kipton Moravec AE5IB
"Always do right; this will gratify some people and astonish the rest."
--Mark Twain