At 04:11 PM 23/12/2010, you wrote:
>?Hi all,
>
>For an AC transfer switch application, I am searching for a relay with the
>following basic specifications :
>
>- single pole contact
>- contact-to-contact gap of at least 3mm
>- maximum switching current/voltage 30A to 40A @ 250-260VAC
>- bi-stable 12VDC coil
>- preferably PCB mounted

Here is one:-
http://www.kgtechnologies.net/PDF/KG-K100_Latching_Relay.pdf

Doesn't look cheap.

>I did not expect that relays with large contact-contact gaps were so rare.=
 I
>found a few examples from mostly German manufacturers, but these do not
>comply to all needed specifications, or are just too expensive.
>
>Does someone have any pointers and/or experience with such relays? Does
>anyone know a relay manufacturer with relativily low MOQ requirements (<20=
k)
>to make a custom relay?

It's possible. Similarly spec'd relays are used in some domestic metering
applications. I presume you require safety agency (eg. VDE) listing
(genuine that is, not the counterfeit Ch**a type- like I got stuck with on =
a
fairly large shipment of power relays a few years back-- that bunch (H****a=
)
are still in business with a large web presence). 8-(

The construction used in metering has a rather brief lifespan, maybe 10,000
operations total rated electrical life.


>Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the rewar=
d"
speff@interlog.com             Info for manufacturers: http://www.trexon.co=
m
Embedded software/hardware/analog  Info for designers:  http://www.speff.co=
m



--=20
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