> Most the relays I've found do not include an inductive load spec
>
> 24VDC coil
> 20A contacts, inductive
> 277VAC switched voltage
> SPST-NO
>
> Ive found several that spec the contacts resistive, but not inductive.  I
> know that inductive is hard on the contacts, for arcing, so I am surprise=
d
> I havent seen it on the data sheets
>

I think it's difficult to spec. With a pure inductor as a load, opening
the contacts theoretically make the voltage go to infinity, which is
difficult for the relay to handle. The arc has to dissipate the energy
that's in the inductor ((L*I^2)/2). Depending on the inductance, this can
be a substantial amount of energy to dissipate. It's nicer to put a
snubber across the contacts and let IT dissipate the energy. The snubber
then limits the voltage across the contacts as they are opening.

Good luck!

Harold



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