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Posted By kormsen on 18 Feb 2010 02:16 PM
during the years i found out, that a reed, that is switching just one turnoutmotor holds for years. while one, that has two or more hooked on, burns out after a couple of months.


Which is why our reeds trip relays to do the heavy work.
 

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Posted By toddalin on 18 Feb 2010 02:28 PM
Posted By kormsen on 18 Feb 2010 02:16 PM
during the years i found out, that a reed, that is switching just one turnoutmotor holds for years. while one, that has two or more hooked on, burns out after a couple of months.


Which is why our reeds trip relays to do the heavy work.


how and with what parts does one make or build that?
 

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Posted By kormsen on 18 Feb 2010 02:38 PM
Posted By toddalin on 18 Feb 2010 02:28 PM
Posted By kormsen on 18 Feb 2010 02:16 PM
during the years i found out, that a reed, that is switching just one turnoutmotor holds for years. while one, that has two or more hooked on, burns out after a couple of months.


Which is why our reeds trip relays to do the heavy work.


how and with what parts does one make or build that?



It varies with the application. What are you trying to accomplish so we can best assess how to do it?

The included schematic shows how to wire two turnouts to throw in opposite directions simultaneously. If you want them to throw in the same direction, turn one of the diodes around so they face the same way. Note that the reed throws the relay that in turn throws the turnouts. The relay can actually be any voltage that is convenient and if you use 16-~24 volt ac relays you can use the ac source that you use for the turnouts.
 

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Posted By kormsen on 19 Feb 2010 04:06 AM
well, as i am not quite sure, that i understood ...

option "A" is what i am using now.
i think, you meant me to change to option "C". right?





Yes, option C.

Most reed switches are good to 100 milliamps with the good (big) ones maybe capable of as much as 1 amp. Two LGB turnout motors can easily draw 1 amp momentarily. But you can easily find relays with contacts rated for 5 amps or more. Try to find a relay that requires less than 100 mA to drive and the reed switch should live forever.

I actually use the reed switches to trip 555 chips that in turn trip the relays. This way I can set the turnouts to throw for ~1 second regardless of how quickly the train is traveling. I also use the other poles of the relay to "lock out" the opposing reed switch used in my leap frog. This way if a train parks over a reed switch, the other reed switch cannot be activated simultaneously feeding + & - 16 volts (32 volt potential) though the turnouts.
 

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Hi Folks,

What I do is described under "Contact Protection" on the following page:
http://www.ceejay.com/aler26.html
in diagram: http://www.ceejay.com/img_aler/aler27_0.gif , the last example annotated "diode." (The diode is positioned against the normal flow of DC across the reed.) The "varistor" example is what I will be trying next on my AC circuits once I figure out how to rate them.

Thanks for the varistor (MOV) info!

Take care, Joe.
 

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"Extra" Switch Driver ??

I don't quite understand the "Extra" 12010 switch driver. I think I understand the wiring. I see that the 2 existing switches have 12010 drivers mechanically connected to the respective switches. Is the "Extra" Driver free-standing?

I'm not really smart enough to understand it, or maybe not?
 

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When making more than one relay activate at the same time, be sure to use a Transformer with over 1 amp output rating. The LGB transformer for the EPL drive is rated at 500ma.
If running some lights then full power is not available for the EPL drive. I use the LGB booster for mine.
 

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Yes, it does. krs told me that his illustration is about 10 years old. He indicated that the more modern layout would eliminate the need for reed switches and associated magnet on the locomotive. He said that some German company had come up with it and that he would let me know, once he finds it. He says it works. So I'm kind of waiting for him to get back with me. But, in the meantime, I'm (impatiently) looking for anybody else who might have come across this "modern" layout that krs is talking about.
 

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By the way, do the reed switches, when actuated, change the relays in the 12030 (12070)? I'm trying to trace the logic of the circuit. I might be able to beat the time it takes those monkeys to write a Shakespeare sonnet. I'm in no hurry! :p
 

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Biggest issue with the 12030 and 12070 is both switches inside do not reverse at the same time, therefore creating a short for a small period of time. Older supplies did not care, but the newer supplies will see this short and shut down!!
I would suggest using the more robust 12 volt car relays which have both contacts disengaging before engaging the opposite contact.
Also there are reversing modules that use mosfets and are more adept for reversing than mechanical relays. Mechanical devices change state in milliseconds, mosfets are in microseconds (a thousand times faster).
 

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The older supplies were just transformers feeding a diode bridge and then big Capacitors to filter out the ripple. These do not monitor current but do have fuses/breakers which are 'slow".



Newer supplies do not have a big A/C transformer, they use an electronic circuit to create the voltage at a constant value and s short can cause the output to shutdown via internal sensors. Electronic sensors are a thousand times faster than a fuse or circuit breaker.
 

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Posted By eheading on 24 Aug 2009 07:17 AM
I gotta say, following this thread, it's the best advertisement for battery power I've seen in a long time!!






Really!
I tried battery power about 5 years ago and found it much too restrictive in many ways for my liking.


As I mentioned earlier - for any of the option discussed here one does the wiring once - so I don't see this as an issue at all.
But each to his own.
 

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It's been a long time since I communicated with you, but you have been an invaluable help and I have been running the reverse loop for quite some time. Now it happened that the loop with the single switch motor stopped switching. Something suddenly stopped working. I don't know what. The other loop (with the two switch motors) works just fine. I can't believe that both diodes stopped working. And I don't get the 19V reading acrosss the 2 diodes on the effected side as I do the on the working side!? Any ideas??
 
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