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2010-01-09 by Steve Hodge
Is it safe to assume a switch is break before make if not specified in the data sheet? Steve __________ Information from ESET Smart Security, version of virus signature database 4757 (20100109) __________ The message was checked by ESET Smart Security. http://www.eset.com
2010-01-10 by MoreOrLess
--- In AVR-Chat@yahoogroups.com, "Steve Hodge" <steve@...> wrote: > > Is it safe to assume a switch is break before make if not specified in the > data sheet? Steve > > > __________ Information from ESET Smart Security, version of virus signature > database 4757 (20100109) __________ > > The message was checked by ESET Smart Security. > > http://www.eset.com > Recalling how most double-throw toggle switches work, yes. That is also true for most rotatory switches. That said, it is just a judgment call. What kind of switch are you talking about? Any manufacture names or logos or part numbers? Mike
2010-01-10 by MoreOrLess
--- In AVR-Chat@yahoogroups.com, "Steve Hodge" <steve@...> wrote: > > Thanks, Mike. The part is a DPDT on-on toggle, Mountain Switch p/n > 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that > Mountain Switch and Mouser are related, not just by identical p/n's but also > by the fact that a google on the former always leads to the latter. > > > > Steve > I have taken switches like that apart and all have had an arm with contacts on both sides goes back and forth, to and fro, with the movement of the bat handle. Not being able to be two places at the same time... You get the picture. That said, if you took a low current fuse, say 1/10 or 1/100 amp job and connected a battery post through the fuse and to one of the outside terminals of the switch, then the other outside terminal of the switch back to the other post of the battery. Now flipped the switch back and forth, how many times, pick a number, 1, 10 or 100, the fuse will still be good. Two possibilities. One, its break before make. Two, the switch never makes long enough to blow the fuse but that I think is unlikely. The make before break would never be long enough to do any good, so what would be the use. Good luck and don't burn the house down, Mike
2010-01-10 by Steve Hodge
Thanks, Mike. The part is a DPDT on-on toggle, Mountain Switch p/n 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that Mountain Switch and Mouser are related, not just by identical p/n's but also by the fact that a google on the former always leads to the latter. Steve
From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf Of MoreOrLess Sent: Saturday, January 09, 2010 5:26 PM To: AVR-Chat@yahoogroups.com Subject: [AVR-Chat] Re: break before make --- In AVR-Chat@yahoogroups.com <mailto:AVR-Chat%40yahoogroups.com> , "Steve Hodge" <steve@...> wrote: > > Is it safe to assume a switch is break before make if not specified in the > data sheet? Steve > > > __________ Information from ESET Smart Security, version of virus signature > database 4757 (20100109) __________ > > The message was checked by ESET Smart Security. > > http://www.eset.com > Recalling how most double-throw toggle switches work, yes. That is also true for most rotatory switches. That said, it is just a judgment call. What kind of switch are you talking about? Any manufacture names or logos or part numbers? Mike __________ Information from ESET Smart Security, version of virus signature database 4757 (20100109) __________ The message was checked by ESET Smart Security. http://www.eset.com [Non-text portions of this message have been removed]
2010-01-10 by blue_eagle74
It is bad to assume anything. It causes problems. Most switches are break before make. The make before break also cost more. But dont relay on price to decide. If you don't have a datasheet you will have to do tests to find out what it is. Brian --- In AVR-Chat@yahoogroups.com, "Steve Hodge" <steve@...> wrote:
> > Is it safe to assume a switch is break before make if not specified in the > data sheet? Steve > > > __________ Information from ESET Smart Security, version of virus signature > database 4757 (20100109) __________ > > The message was checked by ESET Smart Security. > > http://www.eset.com >
2010-01-10 by MoreOrLess
> The part is a DPDT on-on toggle, Mountain Switch p/n > 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that > Mountain Switch and Mouser are related, not just by identical p/n's but also > by the fact that a google on the former always leads to the latter. > > Steve Going to http://www.mouser.com/ProductDetail/Mountain-Switch/108-0043-EVX/?qs=pLI900sz1U7JZJS6Rjho%252bA%3d%3d Gives you the "Specifications" tab. Clicking on the "Documentations" tab gives you http://www.mouser.com/ProductDetail/Mountain-Switch/108-0043-EVX/?qs=pLI900sz1U7JZJS6Rjho%252bA%3d%3d Clicking on "Data Sheet" gives you http://www.mouser.com/catalog/specsheets/MS-100887.pdf This says nothing about being a make-before-break switch. These being $2.81 each, buy two or one extra switch, take one apart by prying out the tabs down the side beneath the mounting threads. Then you should probably tell what kind of break it is. You may be able to get this switch back together but the extra one was in case you cannot, you will still have a good switch or switches. Mike
2010-01-10 by BobGardner@aol.com
I've never imagined a make before break toggle switch. A three position center off toggle id certainly break before make. I always speced a make before break rotary switch to use where I wanted to make sure there wasnt a momentary 'no input' condition if the computer happened to read the switch right during the transition. [Non-text portions of this message have been removed]
2010-01-10 by Andrew Mathison
Hi MoreOrLess its better to use an AND gate to check such things with a LED output.... Some switches are designed to be make before break, and moving the switch fast may not allow the fuse enough time to heat up and burn through......but if the AND gate gets a high from both legs of the switch, it will flash the LED, especially easily seen if a cap is placed to store some energy each time the AND gate switches.... I have not discussed the circuit at great length, a resistor will also be needed to reduce current to the LED.....but from my head all you need is a 5 volts supply, a single two input AND gate, a small cap, a resistor and a LED......and a plug board to mount things on!! regards Andy -------------------------------------------------------------------- I have taken switches like that apart and all have had an arm with contacts on both sides goes back and forth, to and fro, with the movement of the bat handle. Not being able to be two places at the same time... You get the picture. That said, if you took a low current fuse, say 1/10 or 1/100 amp job and connected a battery post through the fuse and to one of the outside terminals of the switch, then the other outside terminal of the switch back to the other post of the battery. Now flipped the switch back and forth, how many times, pick a number, 1, 10 or 100, the fuse will still be good. Two possibilities. One, its break before make. Two, the switch never makes long enough to blow the fuse but that I think is unlikely. The make before break would never be long enough to do any good, so what would be the use. Good luck and don't burn the house down, Mike Greetings from Andy Mathison [Non-text portions of this message have been removed]
2010-01-10 by Steve Hodge
Andy, that sounds like a great suggestion. I'll order a few extra switches and subject them to this test, as well as taking one apart. Thanks for everyone's help. Steve
From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf Of Andrew Mathison Sent: Sunday, January 10, 2010 2:52 AM To: AVR-Chat@yahoogroups.com Subject: Re: [AVR-Chat] Re: break before make Hi MoreOrLess its better to use an AND gate to check such things with a LED output.... Some switches are designed to be make before break, and moving the switch fast may not allow the fuse enough time to heat up and burn through......but if the AND gate gets a high from both legs of the switch, it will flash the LED, especially easily seen if a cap is placed to store some energy each time the AND gate switches.... I have not discussed the circuit at great length, a resistor will also be needed to reduce current to the LED.....but from my head all you need is a 5 volts supply, a single two input AND gate, a small cap, a resistor and a LED......and a plug board to mount things on!! regards Andy ---------------------------------------------------------- I have taken switches like that apart and all have had an arm with contacts on both sides goes back and forth, to and fro, with the movement of the bat handle. Not being able to be two places at the same time... You get the picture. That said, if you took a low current fuse, say 1/10 or 1/100 amp job and connected a battery post through the fuse and to one of the outside terminals of the switch, then the other outside terminal of the switch back to the other post of the battery. Now flipped the switch back and forth, how many times, pick a number, 1, 10 or 100, the fuse will still be good. Two possibilities. One, its break before make. Two, the switch never makes long enough to blow the fuse but that I think is unlikely. The make before break would never be long enough to do any good, so what would be the use. Good luck and don't burn the house down, Mike Greetings from Andy Mathison [Non-text portions of this message have been removed] __________ Information from ESET Smart Security, version of virus signature database 4757 (20100109) __________ The message was checked by ESET Smart Security. http://www.eset.com __________ Information from ESET Smart Security, version of virus signature database 4757 (20100109) __________ The message was checked by ESET Smart Security. http://www.eset.com __________ Information from ESET Smart Security, version of virus signature database 4758 (20100110) __________ The message was checked by ESET Smart Security. http://www.eset.com [Non-text portions of this message have been removed]
2010-01-10 by Zack Widup
Another way to go about this is just to connect a digital multimeter with a continuity "beep" function across the outer switch terminals and flip the switch back and forth. If you don't hear a "beep" it's break before make. I have a quantity of DPDT on-off-pressure*on (in one position the switch stays on and in the opposite position when you release pressure on it, it goes back to center). They are of unknown origin; I believe I got them from All Electronics. They are all break-before-make. Zack On Sat, Jan 9, 2010 at 8:21 PM, MoreOrLess <Brewskister@gmail.com> wrote: > > > > > --- In AVR-Chat@yahoogroups.com <AVR-Chat%40yahoogroups.com>, "Steve > Hodge" <steve@...> wrote: > > > > Thanks, Mike. The part is a DPDT on-on toggle, Mountain Switch p/n > > 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that > > Mountain Switch and Mouser are related, not just by identical p/n's but > also > > by the fact that a google on the former always leads to the latter. > > > > > > > > Steve > > > > I have taken switches like that apart and all have had an arm with contacts > on both sides goes back and forth, to and fro, with the movement of the bat > handle. Not being able to be two places at the same time... You get the > picture. > > That said, if you took a low current fuse, say 1/10 or 1/100 amp job and > connected a battery post through the fuse and to one of the outside > terminals of the switch, then the other outside terminal of the switch back > to the other post of the battery. > > Now flipped the switch back and forth, how many times, pick a number, 1, 10 > or 100, the fuse will still be good. Two possibilities. One, its break > before make. Two, the switch never makes long enough to blow the fuse but > that I think is unlikely. The make before break would never be long enough > to do any good, so what would be the use. > > Good luck and don't burn the house down, > Mike > > > [Non-text portions of this message have been removed]
2010-01-10 by Andrew Mathison
Dear Zack Widup the idea is really good if the meter has some quality to it, some of the cheaper ones I have (ok to check a voltage etc) used may not work well enough i feel..... The AND gate version should work at speeds far in excess of the human finger speeds.....but is more work to make......I would still use your idea first!!! Many thanks Andy --------------------------------------- Another way to go about this is just to connect a digital multimeter with a continuity "beep" function across the outer switch terminals and flip the switch back and forth. If you don't hear a "beep" it's break before make. I have a quantity of DPDT on-off-pressure*on (in one position the switch stays on and in the opposite position when you release pressure on it, it goes back to center). They are of unknown origin; I believe I got them from All Electronics. They are all break-before-make. Zack On Sat, Jan 9, 2010 at 8:21 PM, MoreOrLess <Brewskister@gmail.com> wrote: > > > > > --- In AVR-Chat@yahoogroups.com <AVR-Chat%40yahoogroups.com>, "Steve > Hodge" <steve@...> wrote: > > > > Thanks, Mike. The part is a DPDT on-on toggle, Mountain Switch p/n > > 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that > > Mountain Switch and Mouser are related, not just by identical p/n's but > also > > by the fact that a google on the former always leads to the latter. > > > > > > > > Steve > > > > I have taken switches like that apart and all have had an arm with contacts > on both sides goes back and forth, to and fro, with the movement of the bat > handle. Not being able to be two places at the same time... You get the > picture. > > That said, if you took a low current fuse, say 1/10 or 1/100 amp job and > connected a battery post through the fuse and to one of the outside > terminals of the switch, then the other outside terminal of the switch back > to the other post of the battery. > > Now flipped the switch back and forth, how many times, pick a number, 1, 10 > or 100, the fuse will still be good. Two possibilities. One, its break > before make. Two, the switch never makes long enough to blow the fuse but > that I think is unlikely. The make before break would never be long enough > to do any good, so what would be the use. > > Good luck and don't burn the house down, > Mike > > > [Non-text portions of this message have been removed] ------------------------------------ Yahoo! Groups Links Greetings from Andy Mathison [Non-text portions of this message have been removed]
2010-01-10 by Zack Widup
Yeah, I have three DMM's around here - one I paid about $100 for 30 years ago (I forget the brand), a $25 cheapie and a newer Fluke. Actually, the first one mentioned would work out best because I found out the Fluke has some kind of sample rate on the continuity test and may miss a very short duration short-circuit. I discovered this when I wrote a Morse code beacon keyer program for an AVR and tried to test it with the Fluke generating beeps. It all came out garbled Morse. When I used the first one, it beeped just fine. Zack On Sun, Jan 10, 2010 at 11:02 AM, Andrew Mathison < andrewdavid.mathison@freenet.de> wrote: > > > Dear Zack Widup > > the idea is really good if the meter has some quality to it, some of the > cheaper ones I have (ok to check a voltage etc) used may not work well > enough i feel..... > The AND gate version should work at speeds far in excess of the human > finger speeds.....but is more work to make......I would still use your idea > first!!! > > Many thanks > > Andy > --------------------------------------- > > Another way to go about this is just to connect a digital multimeter with a > continuity "beep" function across the outer switch terminals and flip the > switch back and forth. If you don't hear a "beep" it's break before make. > > I have a quantity of DPDT on-off-pressure*on (in one position the switch > stays on and in the opposite position when you release pressure on it, it > goes back to center). They are of unknown origin; I believe I got them from > All Electronics. They are all break-before-make. > > Zack > > On Sat, Jan 9, 2010 at 8:21 PM, MoreOrLess <Brewskister@gmail.com<Brewskister%40gmail.com>> > wrote: > > > > > > > > > > > --- In AVR-Chat@yahoogroups.com <AVR-Chat%40yahoogroups.com> <AVR-Chat% > 40yahoogroups.com>, "Steve > > > Hodge" <steve@...> wrote: > > > > > > Thanks, Mike. The part is a DPDT on-on toggle, Mountain Switch p/n > > > 108-0043-EVX, which is also the Mouser p/n. I have the odd feeling that > > > Mountain Switch and Mouser are related, not just by identical p/n's but > > also > > > by the fact that a google on the former always leads to the latter. > > > > > > > > > > > > Steve > > > > > > > I have taken switches like that apart and all have had an arm with > contacts > > on both sides goes back and forth, to and fro, with the movement of the > bat > > handle. Not being able to be two places at the same time... You get the > > picture. > > > > That said, if you took a low current fuse, say 1/10 or 1/100 amp job and > > connected a battery post through the fuse and to one of the outside > > terminals of the switch, then the other outside terminal of the switch > back > > to the other post of the battery. > > > > Now flipped the switch back and forth, how many times, pick a number, 1, > 10 > > or 100, the fuse will still be good. Two possibilities. One, its break > > before make. Two, the switch never makes long enough to blow the fuse but > > that I think is unlikely. The make before break would never be long > enough > > to do any good, so what would be the use. > > > > Good luck and don't burn the house down, > > Mike > > > > > > > > [Non-text portions of this message have been removed] > > ------------------------------------ > > Yahoo! Groups Links > > Greetings from > > Andy Mathison > > > [Non-text portions of this message have been removed] > > > [Non-text portions of this message have been removed]
2010-01-11 by Dave McLaughlin
Hi Zack, These type of switches are quite common. You often see then referred to as ON-OFF-(ON). The bracketed on means momentary which is what you have there. Dave...
-----Original Message----- From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf Of Zack Widup Sent: 10 January 2010 22:46 To: AVR-Chat@yahoogroups.com Subject: Re: [AVR-Chat] Re: break before make I have a quantity of DPDT on-off-pressure*on (in one position the switch stays on and in the opposite position when you release pressure on it, it goes back to center). They are of unknown origin; I believe I got them from All Electronics. They are all break-before-make. Zack