> > If the relay is overloaded, it will not last as long, but relays don't
> > last forever. =A0If it is slightly overloaded, the life will be reduced
> > slightly. =A0Even grossly overloaded, the relay might work for a few
> > cycles before the contacts burn out. =A0So you are moving along a curve=
,
> > not going from a binary "in spec, works" to "out of spec, fails."
>=20
>=20
> Agreed, but I need a more deterministic path than "Try it and see what ha=
ppens".
>=20
> For this application, 10k cycles under full load would be a lifetime.

A common way of dealing with a high current application is to have two sets=
 of contacts in parallel, and set up so one contact closes before the other=
, and the one that closes late opens early on release. This then allows the=
 late close/early open contacts to do their thing without arcing, and so ca=
rry most of the current in normal operation, while the early close/late ope=
n contacts become sacrificial in the closing current peak, and opening arc.=
 I believe a properly set up relay uses different contact materials for the=
 two sets, which are designed for the respective purposes.
--=20
Scanned by iCritical.

--=20
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