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Offline aos  
#1 Posted : 31 December 2013 17:43:58(UTC)
aos

Scotland   
Joined: 03/08/2008(UTC)
Posts: 524
Location: Livingston, Scotland
I recently bought a batch of encapsulated miniature reed switches and magnets from a Rapid Online, a company in England. The reason I did this is that the cost of the Marklin reed switches is pretty much prohibitive.

I have been able to mount the reed switches under the track sections and the magnets will still activate the reed switches if I mount them low enough (still plenty of clearance above the track). I am using them to control the setting of 7188 light signals.

All seems to work ok for a while and then the following symptom occurs:
The setting of the signal seems to become “jammed” in one position as though the reed switch has fused itself together inside its casing. Attempting to move the little silver lever in the opposite direction meets with resistance and it springs back again. The solenoid is therefore being definitely powered continually.

If there any electrical wizards out there among you, please take a look at the technical specification via this link and let me know if I have dropped a clanger in buying them.

I am not an electrician and so do not know if they are adequate enough. Could there be another reason for the reed switch to be acting up? The reed switch in question is 60-0511 (3rd column).

Much appreciated. Alan

http://www.rapidonline.c...-Reed-Switch-N-o-60-0511


Offline Renato  
#2 Posted : 31 December 2013 18:49:15(UTC)
Renato

Italy   
Joined: 19/03/2004(UTC)
Posts: 976
Location: Gorizia, Italy
Hi Alan,

It seems to me as during the switching the signal absorbs more than 0.5 A and that is the reason why the plastic housing of the reed relay has fused and consequently the reed contact is permanently in closed position.

If I remember well, during the switching the solenoid consumption is about 10 VA for a very short time (it means: 10 VA : 16 V = 0.625 A and this value exceeds the Switching current (max.) of 0.5 A). Therefore the reed relay is not able to open the contact, the solenoid of the signal is permanently energized and also the reed heats up till the fusion of the plastic.

Maybe an higher value of 1 A could make the difference.

Even better solution: the reed relay is connected to an auxiliary relay which is used to swith the signal.

Hope this explanation is clear and helpful for you.

Cheers and Happy New Year

Renato

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Offline aos  
#3 Posted : 31 December 2013 19:06:09(UTC)
aos

Scotland   
Joined: 03/08/2008(UTC)
Posts: 524
Location: Livingston, Scotland
Hi Renato, I thought might be the case. I shall contact the supplier and see if they have some more robust reed switches. Looking at the Marklin catalogue, I see that the 7555 Reed switch has a maximum current capacity of 2 amps. I suppose that is the difference. Thanks, Alan
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Offline cookee_nz  
#4 Posted : 01 January 2014 00:24:06(UTC)
cookee_nz

New Zealand   
Joined: 31/12/2010(UTC)
Posts: 3,948
Location: Paremata, Wellington
Originally Posted by: aos Go to Quoted Post
Hi Renato, I thought might be the case. I shall contact the supplier and see if they have some more robust reed switches. Looking at the Marklin catalogue, I see that the 7555 Reed switch has a maximum current capacity of 2 amps. I suppose that is the difference. Thanks, Alan


Alan,

Regardless of the current rating, the general recommendation is not to switch accessories such as signals and turnouts directly from a reed switch due to the arcing and burning of contacts, as much from the very small size of the contacts as anything else.

You will achieve much longer life by going through an intermediate solid-state device.

A simple example would be feeding the Reed Switch to a driver transistor, and using that device in turn to actually switch the magnet.

I'm sure I've seen a really simple circuit for doing this, and it's like only 2 or 3 actual components. I will have seen it either in Tom Catherall's Digital Newsletter, or one of Rutger Friberg's Model Railroad Electronics books

Or even possibly posted here previously by one of our electronic boffins? While I'm comfortable working with electronics, I simply don't do enough of it to recommend the specific components required - but possibly someone else will come to the rescue. Clappers ( clapcott Offline ), you have something in mind maybe??

To give you an idea, here's a really good and simple explanation with a neat little animation of how a transistor works and can be used to do exactly what you want

In the animation on the above site, the transistor 'Base' is where the Reed Switch would be connected to (low current ie; 5mA), the Collector is your higher current (500mA) from the Trafo, and the Emitter goes off to the Solenoid. This is somewhat simplified, you will need a couple of other components to make it actually work smoothly and reliably and need to get the correct transistor rating but I suggest it's worth having a play with, electronics can be a heap of fun to play with especially in this hobby because you can make all sorts of useful gadgets which you would otherwise pay a lot more to purchase a ready-made module to do the same thing.

Instructables is a great site for all sorts of info.

Good luck, let us know how you go.

Regards

Cookee
NZ
Cookee
Wellington
NZ image
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Offline Lollo  
#5 Posted : 01 January 2014 03:10:50(UTC)
Lollo

New Zealand   
Joined: 22/06/2009(UTC)
Posts: 365
Hi Alan,

I agree with Cookee, you possibly need a low current switch circuit in between, but it is worth tyring a higher rated reed switch.
I use reed switches to control LED light signals in circuit with self made break modules. The reed switch triggers a low current DPTP relay, so the relay contacts switch the higher load current.
The glass encapulated reed switches I use I buy from Jaycar, but there are no specs for these on their web site.
I have painted the glass with rust brown acrylic paint to blend in. I have had no problems at all with the reed switches. Works perfectly.
These are the magnets I am using, very strong probably a lot stronger than the Marklin ones, but you get more magnets for the fraction of the cost.
Apex magnets These are very strong.
Apex magnets The second link are the same size, but these have a lower pull force, and might be a better option.
Shipping is cheap as well.

Regards,
Brian.
Brian
Yaasan's Desktop Station/Railuino & Marklin MS2, DB Era III/IV Diesel & Steam, ESU Loksound/Lokpilot & Lokprogrammer, Marklin mSD, Tam Valley Depot Octopus III Servo Controller.
thanks 3 users liked this useful post by Lollo
Offline kbvrod  
#6 Posted : 01 January 2014 17:52:12(UTC)
kbvrod

United States   
Joined: 23/08/2006(UTC)
Posts: 2,597
Location: Beverly, MA
Resistors.
Offline cookee_nz  
#7 Posted : 01 January 2014 20:39:34(UTC)
cookee_nz

New Zealand   
Joined: 31/12/2010(UTC)
Posts: 3,948
Location: Paremata, Wellington
Originally Posted by: kbvrod Go to Quoted Post
Resistors.


I simply can't Resist the urge to invite you to expand on that contribution. Are we going for the minimalist approach here? BigGrin
Cookee
Wellington
NZ image
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Offline Bigdaddynz  
#8 Posted : 01 January 2014 22:01:56(UTC)
Bigdaddynz

New Zealand   
Joined: 17/09/2006(UTC)
Posts: 18,661
Location: New Zealand
Originally Posted by: cookee_nz Go to Quoted Post
I'm sure I've seen a really simple circuit for doing this, and it's like only 2 or 3 actual components..........Clappers ( clapcott Offline ), you have something in mind maybe??


Somewhere on the forum is the diagram I posted of the circuit using triacs that was used on Bergtalbahn for reed switch load switching, before they were replaced with K83's. I'll see if I can find it.
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Offline Bigdaddynz  
#9 Posted : 01 January 2014 22:04:12(UTC)
Bigdaddynz

New Zealand   
Joined: 17/09/2006(UTC)
Posts: 18,661
Location: New Zealand
The post I made on the forum was one of the first I ever made, but it's probably easier to repost the image file, which I've found on my computer.
Bigdaddynz attached the following image(s):
triac_switch_new.jpg
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Offline kbvrod  
#10 Posted : 01 January 2014 22:55:50(UTC)
kbvrod

United States   
Joined: 23/08/2006(UTC)
Posts: 2,597
Location: Beverly, MA
Originally Posted by: aos Go to Quoted Post
I recently bought a batch of encapsulated miniature reed switches and magnets from a Rapid Online, a company in England. The reason I did this is that the cost of the Marklin reed switches is pretty much prohibitive.

I have been able to mount the reed switches under the track sections and the magnets will still activate the reed switches if I mount them low enough (still plenty of clearance above the track). I am using them to control the setting of 7188 light signals.

All seems to work ok for a while and then the following symptom occurs:
The setting of the signal seems to become “jammed” in one position as though the reed switch has fused itself together inside its casing. Attempting to move the little silver lever in the opposite direction meets with resistance and it springs back again. The solenoid is therefore being definitely powered continually.

If there any electrical wizards out there among you, please take a look at the technical specification via this link and let me know if I have dropped a clanger in buying them.

I am not an electrician and so do not know if they are adequate enough. Could there be another reason for the reed switch to be acting up? The reed switch in question is 60-0511 (3rd column).

Much appreciated. Alan

http://www.rapidonline.c...-Reed-Switch-N-o-60-0511




Offline kbvrod  
#11 Posted : 01 January 2014 23:02:03(UTC)
kbvrod

United States   
Joined: 23/08/2006(UTC)
Posts: 2,597
Location: Beverly, MA
Originally Posted by: cookee_nz Go to Quoted Post
Originally Posted by: kbvrod Go to Quoted Post
Resistors.


I simply can't Resist the urge to invite you to expand on that contribution. Are we going for the minimalist approach here? BigGrin


Hi all,
depends,....old analog would be 16V in your own country,eh>BigGrin Digital would be 19V [today] the reed switch takes what?Blink
No mention of digital.

Dr D


Offline Webmaster  
#12 Posted : 02 January 2014 00:04:09(UTC)
Webmaster


Joined: 25/07/2001(UTC)
Posts: 11,161
With direct analog wiring, the reed needs to handle the power to switch eg a turnout just as egt a momentary contact track would do...

With full digital, it's enough that the reed indicates "closed or not" to an s88.
So using "any" reeds with digital is easier, they just have to close or not by magnetic influence when trains pass...
Juhan - "Webmaster", at your service...
He who asks a question is a fool for five minutes. He who does not ask a question remains a fool forever. [Old Chinese Proverb]
Offline kbvrod  
#13 Posted : 02 January 2014 00:06:14(UTC)
kbvrod

United States   
Joined: 23/08/2006(UTC)
Posts: 2,597
Location: Beverly, MA
Originally Posted by: aos Go to Quoted Post
I recently bought a batch of encapsulated miniature reed switches and magnets from a Rapid Online, a company in England. The reason I did this is that the cost of the Marklin reed switches is pretty much prohibitive.

I have been able to mount the reed switches under the track sections and the magnets will still activate the reed switches if I mount them low enough (still plenty of clearance above the track). I am using them to control the setting of 7188 light signals.

All seems to work ok for a while and then the following symptom occurs:
The setting of the signal seems to become “jammed” in one position as though the reed switch has fused itself together inside its casing. Attempting to move the little silver lever in the opposite direction meets with resistance and it springs back again. The solenoid is therefore being definitely powered continually.

If there any electrical wizards out there among you, please take a look at the technical specification via this link and let me know if I have dropped a clanger in buying them.

I am not an electrician and so do not know if they are adequate enough. Could there be another reason for the reed switch to be acting up? The reed switch in question is 60-0511 (3rd column).

Much appreciated. Alan

http://www.rapidonline.c...-Reed-Switch-N-o-60-0511




Offline clapcott  
#14 Posted : 02 January 2014 00:30:13(UTC)
clapcott

New Zealand   
Joined: 12/12/2005(UTC)
Posts: 2,433
Location: Wellington, New_Zealand
Hi Alan,

If I may take a slightly different slant on your situation. I am not sure you are asking the question with a full perspective.

Personally I consider the use of reed switches as the best of the "easy" train detection systems and when operated within there design specs the most reliable of any of the mechanical electronic devices.

I do echo the observation of others that suggest moving towards the use of the reed_switch as a "control" and not the driver itself
I do not adhere to the "buy a bigger" idea! Aside from the cosmetic issue, you will start to have issues with the loco shoe being physically affected.

However expanding the "reed as a control" tangent, the direction of a "Triac type" circuit is WRONG for someone like yourself (stated not electrician) or anyone who doesn't want to invest in something that only they can understand and fix (assuming component documentation has been kept). If you want an electronic solution (maybe because of cost) then keep it modular and standard.

Now, the real point I am heading towards is that at some time in the future you may be able to make a jump to a holistic control system (In the Marklin world this is an s88's/m83's and supporting controller - 6021/CS1/CS2 , with OR without a PC ). And most of us are horrified to realize that the many and varied bespoke and RIGID electronic solutions we have added have been unnecessarily time consuming AND , in there sum, expensive (usually more expensive than even a s88 and controller - but here the time frame does come into play). Even if cost is important, the versatility offered by a controller managed system is wonderful by not needing to "get under the layout" if you want to change your sequencing.

You have not mentioned your existing controller type - If it is analogue then that slows thing down, however I need to emphasize that you can get started with digital by working on the accessories (signal and point control) and maybe never change the locomotives. Up to a couple of years ago I would have suggested getting a second hand 6021 and 6043 memory (instead of a CS1/CS2) but I have to say that, for someone starting out, I think these days are over and a CS1/CS2 would be the target - unless you NEVER foresee using an advanced controller.

In closing, I am not not sure what your timeline and investment schedule is, but even if you do not see a controller based solution in the immediate future, plan your wiring for easy upgrade - i.e. do not run a wire via the "shortest possible route" between switch and signal, instead identify a nexus area under the layout where, in future, a m83 can be installed using the existing wires and a "bundle" of sensor/reed wires can convirge into a single cable to head for your s88.





Peter
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Offline YannisB  
#15 Posted : 25 January 2014 03:47:05(UTC)
YannisB

United States   
Joined: 22/05/2010(UTC)
Posts: 190
Location: USA
Alan,
I had the exact problem when I tried to switch turnouts with reed switches: the reed fused itself. The way I solved my problem was to use a miniature double throw relay that is triggered by the reed switch and, in turn, switches the signal (or turnout) to the desired setting.
See my postings in "Me and my layout, YannisB" where I show these relays.
I bought them from an online vendor "All Electronics" (www.allelectronics.com). Very reliable vendor, I highly recommend for any electronic needs, and very reasonably priced.
Contact me if you need more details.
Yannis
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Offline quarkhirad  
#16 Posted : 20 January 2023 22:54:05(UTC)
quarkhirad

India   
Joined: 25/05/2012(UTC)
Posts: 52
Location: surat
Originally Posted by: Lollo Go to Quoted Post
Hi Alan,

I agree with Cookee, you possibly need a low current switch circuit in between, but it is worth tyring a higher rated reed switch.
I use reed switches to control LED light signals in circuit with self made break modules. The reed switch triggers a low current DPTP relay, so the relay contacts switch the higher load current.
The glass encapulated reed switches I use I buy from Jaycar, but there are no specs for these on their web site.
I have painted the glass with rust brown acrylic paint to blend in. I have had no problems at all with the reed switches. Works perfectly.
These are the magnets I am using, very strong probably a lot stronger than the Marklin ones, but you get more magnets for the fraction of the cost.
Apex magnets These are very strong.
Apex magnets The second link are the same size, but these have a lower pull force, and might be a better option.
Shipping is cheap as well.

Regards,
Brian.


Hi Brian. I am just looking for using the reed relays to extend the automated railroad grade crossing. I somehow dont like marklins idea of cutting the track in the manual . So any thats a diversion . I did post my question here before i read this article so sorry if it is a repeat.

https://www.marklin-users.net/fo...act-track-vs-reed-relays

so as there my question is if i use the neodymium magnets will is have issues with the digital decoders in the locomotive and points and crossing. It looks like you have used the NON MARKLIN magnet.

Thank you

Khirad







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Offline quarkhirad  
#17 Posted : 21 January 2023 00:06:15(UTC)
quarkhirad

India   
Joined: 25/05/2012(UTC)
Posts: 52
Location: surat
Hey guys sorry i copied the link to a different post Here it is



https://www.marklin-user...-relay---magnet-distance
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