Does anyone know a good part for a latching Low Thermal EMF Relay for small signal applications? I found many Low Thermal EMF Relays but not latching types. Thanks, Randy Evans

The http://www.transmille.co.uk/8500.htm Wim de Jong _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.

That is an assembly but I am looking for an individual relay part that I can put on a PCB. Randy On Fri, Jul 11, 2014 at 7:15 AM, Wim de Jong <wim.de.jong.59@solcon.nl> wrote: > The http://www.transmille.co.uk/8500.htm > > Wim de Jong > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/volt-nuts and follow the instructions there. > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/volt-nuts > and follow the instructions there. >

Hi, The problem is that most low thermal EMF relays (COTO, Picckering etc) use reed contacts for environment reasons, but reeds are not easy to latch. The good news is that the Omron G6 range has the options you require (and just about any other small relay option). for example the G6AK-274P-STLT-US-DC5 which is dual coil latching, 5v coils and low thermal EMF. It's about $10 from Mouser. The critical parts of the number are AK for dual coil latching, AU for single coil latching and STLT for low thermal EMF DCx is coil voltage, between 3 and 28V. Datasheet here http://www.mouser.com/ds/2/307/G6A_0911-4215.pdf HTH, Robert G8RPI. P.S. Relay contact technology is fascinating. I once specified a lamp rated (added cadmium in contacts) version of a relay. It was controlled by a PIC driving 3 linear halogen lamps (see patent US7247429 <http://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=20070724&DB=EPODOC&locale=en_EP&CC=US&NR=7247429B2&KC=B2&ND=5> ). A couple of years in production decided that a single letter change in the part number of the relay didn't matter and saved a couple of dollars. Guess what, we got failures with welded contacts (fortunatly I'd put a thermal cutout in series with the lamps, mostly incase my PIC code fell over, so no fires :-) Took a while before field service caomplained about poor design...... Then there are the low level and power rated relays that use a gold flash over silver. Trouble is if you use it for power they will fail in low level use. A lot of mil-spec relays use this trick and I've seen problems where relay swapping for fault finding has swapped a low level with a power and back. No initial problem, but months later the contacts have gone high. Then there was the supplier who tested all the new relays - under load, DOH! On 11 July 2014 19:15, Randy Evans <randyevans2688@gmail.com> wrote: > That is an assembly but I am looking for an individual relay part that I > can put on a PCB. > > Randy > > > On Fri, Jul 11, 2014 at 7:15 AM, Wim de Jong <wim.de.jong.59@solcon.nl> > wrote: > > > The http://www.transmille.co.uk/8500.htm > > > > Wim de Jong > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > mailman/listinfo/volt-nuts and follow the instructions there. > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

Thanks George, I had looked at that part but the data sheet was confusing. It did not indicate how to specify low thermal emf or indicate what the emf voltage is. Am I just missing it? Thanks again, Randy On Fri, Jul 11, 2014 at 1:58 PM, George Atkinson < robertg8rpi@virginmedia.com> wrote: > Hi, > The problem is that most low thermal EMF relays (COTO, Picckering etc) use > reed contacts for environment reasons, but reeds are not easy to latch. > The good news is that the Omron G6 range has the options you require (and > just about any other small relay option). > for example the G6AK-274P-STLT-US-DC5 which is dual coil latching, 5v coils > and low thermal EMF. It's about $10 from Mouser. The critical parts of the > number are AK for dual coil latching, AU for single coil latching and STLT > for low thermal EMF DCx is coil voltage, between 3 and 28V. > Datasheet here http://www.mouser.com/ds/2/307/G6A_0911-4215.pdf > > HTH, > Robert G8RPI. > > P.S. Relay contact technology is fascinating. I once specified a lamp rated > (added cadmium in contacts) version of a relay. It was controlled by a PIC > driving 3 linear halogen lamps (see patent US7247429 > < > http://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=20070724&DB=EPODOC&locale=en_EP&CC=US&NR=7247429B2&KC=B2&ND=5 > > > ). A couple of years in production decided that a single letter change in > the part number of the relay didn't matter and saved a couple of dollars. > Guess what, we got failures with welded contacts (fortunatly I'd put a > thermal cutout in series with the lamps, mostly incase my PIC code fell > over, so no fires :-) Took a while before field service caomplained about > poor design...... > Then there are the low level and power rated relays that use a gold flash > over silver. Trouble is if you use it for power they will fail in low level > use. A lot of mil-spec relays use this trick and I've seen problems where > relay swapping for fault finding has swapped a low level with a power and > back. No initial problem, but months later the contacts have gone high. > Then there was the supplier who tested all the new relays - under load, > DOH! > > > On 11 July 2014 19:15, Randy Evans <randyevans2688@gmail.com> wrote: > > > That is an assembly but I am looking for an individual relay part that I > > can put on a PCB. > > > > Randy > > > > > > On Fri, Jul 11, 2014 at 7:15 AM, Wim de Jong <wim.de.jong.59@solcon.nl> > > wrote: > > > > > The http://www.transmille.co.uk/8500.htm > > > > > > Wim de Jong > > > > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > > mailman/listinfo/volt-nuts and follow the instructions there. > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > > mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >

In message <CA+u-Crae+cUPJvpZGucn=kT_weaY9dvqJDk9okbL9zFS9vNLFw@mail.gmail.com>, George Atkinson writes: >The problem is that most low thermal EMF relays (COTO, Picckering etc) use >reed contacts for environment reasons, but reeds are not easy to latch. That's actually not true, Bell labs made latching versions as one of the first things, because that was the big power-saving in telephony switching. However, the latching version came with a polarity requirement, you send current one way to latch and the other to unlatch, and that either meant having two coils would opposite or significant more complexity in the relay circuit in the driving registers. Therefore they went back to the old "holding coil" model instead. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

Hi Randy, The datasheet does not break it down completely but experince of breaking down their numbers, deduction (comparing catalog part numbers for low level and low thermal relays) and common sense indicates that the TLT indicates low thermal EMF. They don't specify levels, but with this part number as a starting point some websearching my get the info, or contact OMRON direct. Robert G8RPI. On 12 July 2014 01:40, Randy Evans <randyevans2688@gmail.com> wrote: > Thanks George, > > I had looked at that part but the data sheet was confusing. It did not > indicate how to specify low thermal emf or indicate what the emf voltage > is. Am I just missing it? > > Thanks again, > > Randy > > > On Fri, Jul 11, 2014 at 1:58 PM, George Atkinson < > robertg8rpi@virginmedia.com> wrote: > > > Hi, > > The problem is that most low thermal EMF relays (COTO, Picckering etc) > use > > reed contacts for environment reasons, but reeds are not easy to latch. > > The good news is that the Omron G6 range has the options you require (and > > just about any other small relay option). > > for example the G6AK-274P-STLT-US-DC5 which is dual coil latching, 5v > coils > > and low thermal EMF. It's about $10 from Mouser. The critical parts of > the > > number are AK for dual coil latching, AU for single coil latching and > STLT > > for low thermal EMF DCx is coil voltage, between 3 and 28V. > > Datasheet here http://www.mouser.com/ds/2/307/G6A_0911-4215.pdf > > > > HTH, > > Robert G8RPI. > > > > P.S. Relay contact technology is fascinating. I once specified a lamp > rated > > (added cadmium in contacts) version of a relay. It was controlled by a > PIC > > driving 3 linear halogen lamps (see patent US7247429 > > < > > > http://worldwide.espacenet.com/publicationDetails/originalDocument?FT=D&date=20070724&DB=EPODOC&locale=en_EP&CC=US&NR=7247429B2&KC=B2&ND=5 > > > > > ). A couple of years in production decided that a single letter change in > > the part number of the relay didn't matter and saved a couple of dollars. > > Guess what, we got failures with welded contacts (fortunatly I'd put a > > thermal cutout in series with the lamps, mostly incase my PIC code fell > > over, so no fires :-) Took a while before field service caomplained about > > poor design...... > > Then there are the low level and power rated relays that use a gold flash > > over silver. Trouble is if you use it for power they will fail in low > level > > use. A lot of mil-spec relays use this trick and I've seen problems where > > relay swapping for fault finding has swapped a low level with a power and > > back. No initial problem, but months later the contacts have gone high. > > Then there was the supplier who tested all the new relays - under load, > > DOH! > > > > > > On 11 July 2014 19:15, Randy Evans <randyevans2688@gmail.com> wrote: > > > > > That is an assembly but I am looking for an individual relay part that > I > > > can put on a PCB. > > > > > > Randy > > > > > > > > > On Fri, Jul 11, 2014 at 7:15 AM, Wim de Jong <wim.de.jong.59@solcon.nl > > > > > wrote: > > > > > > > The http://www.transmille.co.uk/8500.htm > > > > > > > > Wim de Jong > > > > > > > > _______________________________________________ > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > > > mailman/listinfo/volt-nuts and follow the instructions there. > > > > _______________________________________________ > > > > volt-nuts mailing list -- volt-nuts@febo.com > > > > To unsubscribe, go to https://www.febo.com/cgi-bin/ > > > > mailman/listinfo/volt-nuts > > > > and follow the instructions there. > > > > > > > _______________________________________________ > > > volt-nuts mailing list -- volt-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > > and follow the instructions there. > > > > > _______________________________________________ > > volt-nuts mailing list -- volt-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > and follow the instructions there. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. >