RE: [Elecraft] K2 Relay contact resistance
That was 200,000 with (memory check?) 1A on the contacts. You need to use the mechanical numbers, since the current is << 1A. Dan / WG4S / K2 #2456 > Electrical: 200,000 operations min. (at 1,800 operations/hr) ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K2 Relay contact resistance
Ken K3IU wrote: > Electrical: 200,000 operations min. (at 1,800 operations/hr) Eeek. I was intending to set up some software to monitor IBP beacon frequencies for 3mins each. 1 band change every 3 minutes, 5 beacons to get through, call it 2 operations every 15 minutes for each relay involved, so admittedly "only" 8 operations/hr not 1,800, but that still gets me 200,000/8 = 25000 hours, that's about 3 years life expectancy, or admittedly "min" life expectancy... Better hope I manage something closer to Wayne's "millions of switching cycles" :-/ -- "Nosey" Nick Waterman, G7RZQ, K2 #5209. use Std::Disclaimer;[EMAIL PROTECTED] The only thing worse than raining cats and dogs is hailing taxis. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K2 Relay contact resistance
In a message dated 2/12/06 12:07:24 PM Eastern Standard Time, [EMAIL PROTECTED] writes: > K2 s/n 12 in pretty constant use here, particularly in contests. > So far as I can tell, I have no problem with the relays, either in the > basic K2 or in the KAT2. > Perhaps that 'pretty constant use' is the key. IIRC, the original poster said he "dusted off his '1000MP". Which means it has probably been sitting around idle for a long time. Wiping action only works if the relays actually cycle once in a while. 73 de Jim, N2EY ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K2 Relay contact resistance
Hi Stewart I have K2 s/n 12 in pretty constant use here, particularly in contests. So far as I can tell, I have no problem with the relays, either in the basic K2 or in the KAT2. Good luck and 73 Bob N6WG Teh Little Station with Attitude -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Stewart Baker Sent: Sunday, February 12, 2006 4:24 AM To: Elecraft Reflector Subject: [Elecraft] K2 Relay contact resistance Having decided to join the melee trying to work 3Y0X on Peter One Island, I dusted off my FT1000MP. The only time that I use it are on occasions such as this when a separate receiver is useful when working split. I noticed that the receive sensitivity was varying on 20 & 40m, and traced this to the HPF board at the front of the receiver. This board contains 8 miniature relays which do the filter switching. If I tapped the board the received signal strength varied. From notes I found on the web this is a known problem where the solution is to change all 8 relays. I didn't fancy changing these small relays if there was a better solution. I remembered that the FT102 had big problems with people were changing relays by the bucket full. Yaesu don't seemed to have learned the lesson of the FT102 ! A local amateur came up with a fix which consisted of running a small DC current through the contacts to break down any oxide layer that had formed over time. This morning I modified the HPF board to run about 1mA through the contacts. 10 resistors and 2 caps later - End of problem - Fixed The big relays in the KAT100 should not have a problem, but what about the smaller ones in the K2, KAT2 ? As far a I can tell a number of these have only very small AC signals passing through them. None have any DC current flow. It took about 7 years before the problem surfaced with my FT1000MP, I would be interested in comments on whether in the same time scale I might expect to get similar problems with my Elecraft gear. 73 Stewart G3RXQ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K2 Relay contact resistance
Entering into an area where I know little, the following from the Omron web site http://www.omron.com/ecb/products/pry/111/g6h.html Found under "Characteristics Endurance Mechanical: 100,000,000 operations min. (at 36,000 operations/hr) Electrical: 200,000 operations min. (at 1,800 operations/hr) " Not sure whether this relates to the discussion or not... 73, Ken K3IU -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Stewart Baker Sent: Sunday, February 12, 2006 10:11 AM To: Don Wilhelm; Elecraft Reflector Subject: RE: [Elecraft] K2 Relay contact resistance Don, Thanks for your prompt reply. I think that the problem (if there is one) will only show up after a number of years. Maybe 7 years is the magic figure. It also will depend to a great extent on the quality of manufacture, cleanliness etc. I had a look at the Omron G6H data sheet. The 100 million operations are the mechanical service life. For the electrical service life you must look under the Characteristic Data. Unfortunately the electrical service life curves only show 2 graphs. One for a 30VDC and one for a 125VAC, both into a resistive load. There is no definitive data presented for when there is no current flow. Like you, I am not sure if these small relays have a wiping action. Perhaps there is a relay expert on the reflector ? Otherwise as you say - only time will tell the true tale. 73 Stewart G3RXQ On Sun, 12 Feb 2006 08:15:24 -0500, Don Wilhelm wrote: > Stewart, > > All I can say is that K2 SN 00020 is working fine after 5 years with > no relay problems, and in all the K2s that I have worked on, I have > found only one relay failure. > > Relay contact failure can also be prevented by using relays that > possess wiping contacts. I know not how much wiping action exists on > the latching relays used in the K2, but they are speced by the > manufacturer (Omron G6H relay data sheet) for 100 million operations > with 50 milliohms maximum contact resistance. The contacts are gold > plated silver and I would believe they should not normally need cleaning by means of a DC bias. > > Perhaps another couple years on the K2 will give a comparison with the > experience with your MP1000 - only time will tell the true tale. > > 73, > Don W3FPR > > >> -Original Message- >> ... >> This morning I modified the HPF board to run about 1mA through the >> contacts. >> 10 resistors and 2 caps later - End of problem - Fixed >> >> The big relays in the KAT100 should not have a problem, but what >> about the smaller ones in the K2, KAT2 ? As far a I can tell a number >> of these have only very small AC signals passing through them. None >> have any DC current flow. >> >> It took about 7 years before the problem surfaced with my FT1000MP, I >> would be interested in comments on whether in the same time scale I >> might expect to get similar problems with my Elecraft gear. >> >> 73 >> Stewart G3RXQ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K2 Relay contact resistance
Don, Thanks for your prompt reply. I think that the problem (if there is one) will only show up after a number of years. Maybe 7 years is the magic figure. It also will depend to a great extent on the quality of manufacture, cleanliness etc. I had a look at the Omron G6H data sheet. The 100 million operations are the mechanical service life. For the electrical service life you must look under the Characteristic Data. Unfortunately the electrical service life curves only show 2 graphs. One for a 30VDC and one for a 125VAC, both into a resistive load. There is no definitive data presented for when there is no current flow. Like you, I am not sure if these small relays have a wiping action. Perhaps there is a relay expert on the reflector ? Otherwise as you say - only time will tell the true tale. 73 Stewart G3RXQ On Sun, 12 Feb 2006 08:15:24 -0500, Don Wilhelm wrote: > Stewart, > > All I can say is that K2 SN 00020 is working fine after 5 years with no > relay problems, and in all the K2s that I have worked on, I have found only > one relay failure. > > Relay contact failure can also be prevented by using relays that possess > wiping contacts. I know not how much wiping action exists on the latching > relays used in the K2, but they are speced by the manufacturer (Omron G6H > relay data sheet) for 100 million operations with 50 milliohms maximum > contact resistance. The contacts are gold plated silver and I would believe > they should not normally need cleaning by means of a DC bias. > > Perhaps another couple years on the K2 will give a comparison with the > experience with your MP1000 - only time will tell the true tale. > > 73, > Don W3FPR > > >> -Original Message- >> ... >> This morning I modified the HPF board to run about 1mA through >> the contacts. >> 10 resistors and 2 caps later - End of problem - Fixed >> >> The big relays in the KAT100 should not have a problem, but what >> about the >> smaller ones in the K2, KAT2 ? As far a I can tell a number of >> these have only >> very small AC signals passing through them. None have any DC current flow. >> >> It took about 7 years before the problem surfaced with my >> FT1000MP, I would be >> interested in comments on whether in the same time scale I might >> expect to get >> similar problems with my Elecraft gear. >> >> 73 >> Stewart G3RXQ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K2 Relay contact resistance
Stewart, All I can say is that K2 SN 00020 is working fine after 5 years with no relay problems, and in all the K2s that I have worked on, I have found only one relay failure. Relay contact failure can also be prevented by using relays that possess wiping contacts. I know not how much wiping action exists on the latching relays used in the K2, but they are speced by the manufacturer (Omron G6H relay data sheet) for 100 million operations with 50 milliohms maximum contact resistance. The contacts are gold plated silver and I would believe they should not normally need cleaning by means of a DC bias. Perhaps another couple years on the K2 will give a comparison with the experience with your MP1000 - only time will tell the true tale. 73, Don W3FPR > -Original Message- > ... > This morning I modified the HPF board to run about 1mA through > the contacts. > 10 resistors and 2 caps later - End of problem - Fixed > > The big relays in the KAT100 should not have a problem, but what > about the > smaller ones in the K2, KAT2 ? As far a I can tell a number of > these have only > very small AC signals passing through them. None have any DC current flow. > > It took about 7 years before the problem surfaced with my > FT1000MP, I would be > interested in comments on whether in the same time scale I might > expect to get > similar problems with my Elecraft gear. > > 73 > Stewart G3RXQ > ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
