I believe I have all the WECo relay information data sheets and/or a list of models and specs. I saw them the last time I was pulling some data information on WECo. transformers from my stash. I'll take a look later this evening.
Pete, wa2cwa On Thu, 17 Dec 2009 11:30:13 -0700 "JAMES HANLON" <[email protected]> writes: > Jack, > > I don't have the info on the 303J you are after, but John, K2TQN, > gave you good advice. If you can find just one coil winding with > your ohm meter, that's the one to work with. You should be able to > find the normally closed contacts, they will measure very close to > zero ohms. Monitor them while you ramp up voltage on the coil. The > nominal coil operating voltage will probably be either 24 or 48 > volts. If you get up to 48 volts and the contacts have not opened, > reverse the polarity of the voltage and try again. This relay will > have a bias magnet, so you have to get the coil polarity right to > make it operate. The relay should operate on substantially less > voltage than its nominal rated value. It's operating time should be > around 1 millisecond. > > Once the contacts have opened, you can use your ohm meter to find > the "normally open" contact which at that point will be shorted to > the swinger. The swinger will be attached to one of the two pins > you've been monitoring, and the normally open contact will show up > on another pin. > > The mercury-wetted switch inside is probably a WE 226D, judging from > the size of the relay can. That switch is a single-pole, double > throw switch that is of the "non-shorting" type. The swinger will > break free (open circuit) from the normally-closed contact before it > makes to the normally-open contact on its operate cycle. On its > release cycle, it will similarly open up from the normally open > contact before it makes to the normally closed contact. The 226D > switch is rated for a maximum of 3 amps DC current, and it should > switch up to a 50 VA load. Operated within its ratings, it should e > good for more than a billion switcing cycles. It will not "bounce" > or "chatter" on either operate or release. It should sustain more > than 1000 Vac rms across its open contacts, although it shouldn't be > used to switch that much voltage. I've used a similar relay to > switch B+ on the order of 300 volts at around 0.05 amps for keying > purposes with no problem. Insulation resistance of the > open contact should be above 100 megohms. Resistance of the > closed contact should be below 50 milliohms. > > Once upon a time, back in the 70's, I was the supervisor of the Bell > Labs group that was responsible for the design of WE mercury wetted > relays, just in case you are wondering. > > Hope this helps, > > Jim, W8KGI ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Post: [email protected] To unsubscribe, send an email to [email protected] with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
