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Installing a 151 Semaphore ?

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Installing a 151 Semaphore ?
Posted by AirMojo on Wednesday, December 28, 2016 5:01 PM

Hey, I'm getting my trains up and running after almost 20 years !

I have an MTH 30-1075 Semaphore, which is a copy of the Lionel 151 Semaphore... well that's what I think it is... there's nothing on the unit, except an embossed MTH on the underside of the base.

I'm unable to find the box right now... probably buried with all my other train boxes in the attic cubbyhole, which isn't easy to get to.

I think this unit comes with an MTH Track Activation Device TAD, but I can't find it, and it may still be in the box... I think this is similar to the Lionel 153C Contactor... it has 3 wire posts on it.

Can this 151 Semaphore be installed using the screw posts on an O31 switch ?

I know I have an MTH Block Signal (153) installed on one of the other O31 switches.

Or can it be installed directly to the track, like I have done with the two wired signals and the #145 Automatic Gateman instead of using 145C Contactors ?

Thanks for your help!

Also, I'm experimenting with recording some videos using my little Panasonic Lumix camera that has been sitting idle for several years after I got my iPhone.

Looks promising !

Ken H in OH

 

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Posted by Penny Trains on Wednesday, December 28, 2016 6:54 PM

I assume you mean one like I have here on the left:

I have it wired to an insulated track section (O27 in this case) by way of two prewar lock-ons.  Insulated sections are A LOT more reliable than leaf contactors!  (It's hard to see, but over on the far right of the pic is a bell signal also wired to an insulated section.)  I've never had a layout big enough to use turnouts, but from what I've heard and read about them I don't know why the semaphore would cause any problems the block signals would other than maybe a slight drop in voltage.  Maybe they would stay activated until the turnout is switched back?  I'm not sure but what I am sure about is the correct answer will come!

Becky

Trains, trains, wonderful trains.  The more you get, the more you toot!  Big Smile

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Posted by AirMojo on Wednesday, December 28, 2016 7:22 PM

Yes, Becky that's it.

I would prefer not use a contactor... I have used some insulator sections of track... just haven't wired them up in a long time !

I'll dig through my old books, and do some experimenting.

Ken H in OH

KRM
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Posted by KRM on Wednesday, December 28, 2016 7:45 PM

I agree with Becky, that the insulated track sections are the best choice, The only problem is their cost and they are short. So to get around that I make my own by taking apart old track and using the insolation paper on my better newer track. I have tons of old trash track and you can get a lot for next to nothing on the bay if you look. I then like to do at least a four section of insulated track sections to run an accessory. Gives it time to start before the train gets there and end afterwards.
 Last thing I did was on two 252 crossings gates running off of two tracks powered by two different transformers.
 

 http://cs.trains.com/ctt/f/95/t/260122.aspx

See it here.

 

 

 

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Kev, From The North Bluff Above Marseilles IL. Whistling

 

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Posted by AirMojo on Thursday, December 29, 2016 7:44 AM

Okay, I think I figured this out... I think I confused myself by looking at how the 153 signal block (MTH version) was hooked up to the O31 turnout switch, and the three wiring posts on the 151 semaphore (MTH version).

So what I will do is connect the left light post to my light connections that are connected to my ZW transformer CU post (set to 12v--so the bulbs don't burn out with too much voltage), the center ground post will be connected to an insulated outer (ground) track rail, and the right activating arm post will be connected to the center track rail.

Does this sound right ?

Edited: After thinking about this the light on the semaphore will not be lit until the train enters the insulated track, right ?

I think I still want the O31 turnout switch to be used, but not sure.

Ken H in OH

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Posted by BigAl 956 on Thursday, December 29, 2016 9:04 AM

AirMojo
I think I still want the O31 turnout switch to be used, but not sure.

Reverse your conections and this will work right.

There are 3 connections to the Semaphore. The frame is common to the coil and lamp. Then there are connections to the coil and lamp. If you use your transformer power as the common then a 'ground' to the lamp and a switched ground to the coil will have the light on all the time and control the activation coil.

Your O22 switches output a ground on thier control terminals when switched. You can connect one of the terminals to the semafore to activate it when switched a certain way.

If you use an insulated track section to apply ground to the coil then you can activate the signal when a train is on the insulated track. 

This will work more efficently with relays and there are a few books that explain the wiring in more detail.

One tip I followed was to use a bridge rectifier to power the signal via DC instead of AC to eliminate the anoying buzzing sound. However, I found out early on MTH semafores do not like to be powered with bridge rectifiers. In fact I burned two of them up using a rectifier wheras my postwar Lionel 151s worked fine with DC.

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Posted by lionelsoni on Thursday, December 29, 2016 9:52 AM

The 022 turnout does not ground the control terminals (that is, connect them to the common outside rails).  These terminals are connected to the center rail (or the optional fixed voltage) through the solenoids that operate the turnout.  The controller grounds one of the terminals and, as the turnout is thrown, a switch in the turnout open-circuits the solenoid.

The usual way of operating a signal from an 022 exploits the fact that a small lamp (in the signal) connected to a control terminal and returned to ground, does not draw enough current to throw the turnout.  This same method is used in the controller to operate its indicator lights.  I suspect that a semaphore solenoid (returned to ground rather than the center rail or fixed voltage) would draw so much current that this scheme would not be practical.  But it wouldn't hurt to try it.

Bridge rectifiers produce the same DC as any full-wave rectifier.  But they do have the disadvantage that there is no common terminal between input and output.  This disqualifies them from use in a control-rail circuit, powered from an output from a transformer whose common is connected to the track.  If this was not the problem with Al's MTH semaphores, another possibility is that the semaphores' DC resistance was so much lower than their AC impedance that they simply drew more current on DC than they could stand, and should have been operated at a much lower DC voltage.

Bob Nelson

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Posted by AirMojo on Tuesday, January 10, 2017 6:41 PM

Thanks guys !

Thanks BigAl956... I just tested it with the way you suggested, and used an insulated track, placing the insulated track section after one of my 031 switches when the train turns to the left, activiating the 151 arm to go down over the straight ahead track.

Now to get it hooked up for good.

I've been playing around with mounting a small point and shoot camera (Panasonic Lumix) in various cars to record video while the train is moving.

Lots of fun! I wish I had such a setup 20 years ago when my son was into the trains... he would've loved making his own train videos... he's a professional videographer now... can't wait to show him a video once I get it done... but still need to hook up a few more things that never got done back then.

Ken H in Ohio

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Posted by AirMojo on Wednesday, January 11, 2017 11:51 AM

This morning I hooked up my MTH 151 Semaphore, where the left post (for the lamp) is connected to the transformer gound, the right post (for the arm/coil) is attached to an insulated track section (outer rail) that is connected directly after the O31 switch left turn track, and the center post is connected to the transformer power (ZW C post where my other 12v switches and lights are connected).

All seems to be working fine.

However there is sparking from the train wheels when the travel over the insulated track... I assume this is normal, since an electrical connection to the arm/coil is being made due to the positive "ground" connection on the semaphore and the negative insulated track section.

Am I correct ? So to eliminate the "sparking" in the 151 semaphore case, a different type of connection using a relay would be required ?

I have a few other insulated track sections throughout my layout, but they are just used as a simple "switch" connection for the ground connection.

Ken H in OH

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Posted by bridgeengineer on Wednesday, January 11, 2017 7:52 PM

The sparking should be reduced after cleaning the track and also cleaning the wheels on each car, with paper towels and solvent such as paint thinner or mineral spirits.  Heavier cars may contact the rails better, which also would reduce the sparking.  I found over the years that using the insulated rail method can increase the buildup of grime on the car wheels; something about the electrical flow attracting dust and oil and grime.  I prefer to use the trackside infrared detectors, made by both Lionel and MTH, so that power to the signal is independent of the track.  These detectors have contacts for "normally open" and "normally closed" circuits.  For a semaphore, you would use "normally open", meaning the arm would be up and the light would be green until the train comes and causes the detector to close the circuit and lower the arm.  For a block signal, you would connect the green light to "normally closed" and the red light to "normally open".  However, the I/R detectors can seem expensive.

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Posted by AirMojo on Wednesday, January 11, 2017 8:52 PM

Thanks for the response, bridgeengineer...

I'm using a Lionel 685 locomotive with a tender, that's pulling  8 cars... I'll give the wheels a good cleaning and see how that works.

I'm going to have to look into the I/R detectors... sure wish there was a good local train/hobby shop nearby... but I hope to go to a few train shows, and I'll be looking into them and asking questions.

Ken H in OH

 

 

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Posted by lionelsoni on Thursday, January 12, 2017 9:24 AM

This may be the first proposal I've seen to move from control-rail activation to infrared or contactor!  Usually operators are going the other way, to get away from adjustment and reliability problems.

Yes, Ken, everything is working as expected, including the sparking.  That happens whenever the connection through the axles, from wheels on one side of the train to the other, is broken.  Ideally, this should happen only once, as the last wheel set leaves the control rail; so the dirty-rail or dirty-wheel diagnosis is correct; and cleaning wheels and rails (both the control rail and the other outside rail) should make a difference, although there will always be some sparks.

Another thing that might help is to see whether the sparking is greater on one side of the track or the other, and to swap the control rail to the other side if that might make the sparking less obvious on your particular layout.

A relay circuit would just substitute the inductive relay winding for the inductive semaphore winding, but probably wouldn't solve the underlying problem.

(There's no "positive" or "negative" in a circuit like this, nor in most toy-train circuits.  One can call a toy-train frame a "ground," since the chassis of any vehicle is an honorary ground, even though it is not really grounded.  But otherwise, as in the semaphore or the U terminal of a multi-control transformer, the proper term is "common.")

Bob Nelson

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Posted by AirMojo on Thursday, January 12, 2017 2:35 PM

Thanks Bob! I figured the sparking was normal, since everything seems to be working well.

The infrared thing looks interesting... I may try it out someday... but depending on how you can adjust sensitivity or distance of the train, it may be a pain with my three separate tracks, plus one short track with bumpers... it might drive me crazy when other trains are setting it off.

I do like the old school stuff since it seems easier (or possible) to do the repairs myself.

I have a modern 345 Culvert Unloader that no longer works, and I had to have the motherboard replaced shortly after I bought it back around 2000 or so... I suspect the board is fried again... and may be impossible to get the replacement part.

I also have MTH Esso Gas station that wasn't working, but I seemed to have fixed that... but the sound gets activated on it sometimes without actually switching it on, then it will not work again until I power everything off for a few minutes... weird electronics, or some sort of signal getting through the connections.

Thanks for you help... my terminology was never that good even 20 years ago... It's nice to have internet forums to go to for help, especially since there seem to be so little brick-and-mortar trains stores these days.

Ken H in OH

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Posted by bridgeengineer on Tuesday, January 24, 2017 2:54 PM

Infrared detectors may not work in all situations, depending on track arrangement, but reliability has been good for me.  I only have one on my home layout, and it (a Lionel model) has worked satisfactorily for years.  On the large layout we assemble every holiday season at the St. Louis Museum of Transportation, we use about 7 or 8 of them, MTH models.  Sensitivity can be adjusted and they work fine for our double tracks.  Delay (time to turn off) can also be adjusted.  The only problen I've had in four years was that, as I adjusted one of them, it began smoking and never worked again.  All the others have worked fine.

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