Years ago I was faced with an existing design that
loved to weld relay contacts closed. The open circuit
voltage, and the closed circuit current, both fit
within the relays specifications. There was one final
spec, though - the relay contacts had a "VA" (volt
ampere) specifiction. The vendor told me that in this
case, "VA" referred to the open-circuit voltage
multiplied by the closed-circuit current, and that if
you exceeded this multiplied value, the contacts could
weld shut. It seems to be a specification unique to
reed relays, due to the very low thermal mass of the
contacts.
HTH
Dave W8NF
===== In Response to: =====
From: Steve Katz <stevek@jmr.com>
Subject: RE: [BULK] - [Amps] IC-718 and AL-811: Icom
manual misleading, interface necessary according to
Icom technician
amps@contesting.com
When I asked how such damage could occur, given the
specs in the
manual,
the Icom technician told me that the specs as printed
in the manual are
misleading and that the IC-718 send relay can only
handle "16 volts OR
2
amps, not both."
::Did you ask him where the 2 amps would come from, if
there are no
volts?
Maybe Icom's figured a way to make current flow
without any potential,
that
would be really cool. I could convert my car to run
on a zero volt
battery,
as long as it can deliver 1000 amps, I'd be all set.
-WB2WIK/6
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