On 21 Dec 2010 at 12:07, David VanHorn wrote:

> Can anyone point me to a clear, well written guide to relay
> specifications, particularly with regard to reactive loads?
>=20
> I'm looking at a relay in a design, and it's not clear whether or not
> it is being used within spec.  Inrush current is ok, but peak voltage
> is high (few uS at opening).
> One source tells me that because Ipeak * Vpeak is larger than the kVA
> rating that there is a problem, but it doesn't make sense to me in
> that Ipeak and Vpeak cannot occur at the same time.  My Ipeak and
> Vpeak measurements are under absolute worst case conditions, measuring
> many times with the scope, and taking the worst observed value.
>=20
> The more I dig, the fuzzier the ratings seem to become..

Not an exact pointer, but there is some good reading on relays in these Tyc=
o=20
application notes:

http://relays.tycoelectronics.com/appnotes/

--=20
Brent Brown, Electronic Design Solutions
16 English Street, St Andrews,
Hamilton 3200, New Zealand
Ph: +64 7 849 0069
Fax: +64 7 849 0071
Cell: +64 27 433 4069
eMail:  brent.brown@clear.net.nz


--=20
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