Lionel Dwarf Signal #148

If you are using an insulated outside rail block, make sure the track and wheels are clean and that the insulated section is long enough to always have a few wheel sets bridging the outside rails.

thanks - i did clean the track - may try another section of insulated track to see if that helps

thank you agan

ted

Roll a car over the rails exerting slight pressure and see if that helps.

I put pressure on a caboose with heavy die cast wheels.  The green light flickers and sometimes goes out.  If I shift the weight of the car side to side I can get the green light to go out. But when I let the car rest inside insulated block the red light is on for a second then both are on   When I start to move the caboose the green light flickers and then comes on bright .Track is clean 

You've mentioned twice that the track is clean. Have you clean the wheels?? Take a Q-tip and some alcohol and try cleaning the wheels if you haven't.

Can you share your wiring with us, what else is in play to activate the signal.  If all you are using is the insulated track, both lights will come on...

Marty

here ia the sketch of how i tried it

i cleaned the wheels and till have the problem - i tired it with a spare die cast truck and weight on top - still did not help- i think it may be in the signal

I'm not sure how that signal works. I've never seen one. But looking at your sketch it looks like you should have a dead short. The black and red look like they're going to the same terminal? In any case the green is not going to be activated with that type of a set up. You can get the red to go on and off with the insulated rail but you aren't going to get the green to go on and off.  There are ways to do it with relays, but the easiest is a 153 contact switch or the MTH equivalent is even better.

The way you have it wired in first pic schematic is just wrong the way you have it wired in II schematic will make both lights come on. You have to move the common to the Transformer the red to the first insulated track then you have to make an insulated track further down the line and add the green to it now your red light of go on when the train hits the first and then the green light go on when it hits the second 

Ted

On the 2 sections of 10" track inside the your 5" isolated sections, Did you remove the ground straps underneath the 10" track? I've had to do this with my track to get Fastrack crossing gates to function correctly when I added 10" sections to move the isolation track out further. Having your black wire connected to the top rail in the upper drawing makes sense to me, but with the ground straps in place your also grounding the bottom rail essentially shorting out the yellow wire.

Chris

As Train Nut posted above, the insulated rail by itself can automatically complete a circuit, in this case to turn on the red bulb (LED), but it can NOT OPEN a circuit to turn off the green bulb.  You need a relay*.  This has been discussed on here quite a bit.  Do a search for 153 Block signal wiring.

And do use auxiliary power, not track power.

Bill

* yes I know there is a way of doing it without a relay but as I recall it's much more  complicated than using a relay plus it really doesn't completely turn off the green light it just dims it.

I had to use a relay to get mine to work with a DZ 2500.  Now works great.  Used the DZ1008.

the insulated track sections outside rails are not "connected" they are the insulated sections that lionel sells

i followed the instructions for the #148 signal, if i need a relay or other solution - why does lionel show the fast track connection like i have tried to connect?  or does it mean that the red and green lights will be on when the train in the insulating block?

The insulated track section will activate the red light and turn it on and off as the train passes through, but the green light will stay on constantly with that type of setup.

Ted i have the same problem with mine as well!! I have tried everything still does not work right!!  

And i stand corrected....   I looked at the updated manual online for that signal. It does indeed say it will change from green to red and then back to green again. Maybe there is a relay built in that particular signal now.  Are sure you have a current new model of it with the fast track directions included with it. You didn't pick up an old signal and look online for the manual did you?  I'm going to look at it again after supper and see if I can figure anything out. Probably not.

There are at least 3 versions of the 148 dwarf signal. The latest (still available from Lionel) uses LED's rather than light bulbs and has 3 wires; not 4. Here's a link to the owner's manual . I think the original poster has got it wired correctly. It just doesn't do what it's supposed to.

Additionally, im thinking this must be a new model. Because if you look at the old directions from 2011 it clearly states it can only be used with a 153 contactor, infrared activation device, or remote switch hookup.   That model cannot be used with an insulated section.  So I'm still thinking if this is indeed a current model you are using there has to be some kind of relay in it for it to work.

Train nut he is talking about the new dwarf signal with led's has a relay in it suppose to work with insulated track!! 

Oops! Wrong version of the operator's manual. This is the latest version with the LED's.

chessie1971 posted:

Train nut he is talking about the new dwarf signal with led's has a relay in it suppose to work with insulated track!! 

I didnt take my "magic mind reading pills" today!!    He made no mention of it being the new LED model, nor did anyone else until Consolidated Leo's  post which crossed with my most current post saying it must be the new model.  

It does look like you have it hooked up correctly according to their directions.  Thinking it must be a bad internal relay or some other manufacturing problem which would not be surprising at all.. Sounds like others possibly have the same issue.  I would call Lionel and see what they have to say.

Ted, these are pretty dicey lights.  So, FWIW,  Here’s mine on tubular insulated section.  Three wire hookup using a lockon.  Track was cleaned just before video.  I think dirty wheels and/or car weight is causing the issue.  Note it flickers at the same time while the train rolls through.

First my  disclaimer:  I don't have any experience with the LED 148 model.  I do have some experience with similar K-line LED signals.   The circuit used by K-Line  does not turn both LED's on and off.  Rather, the circuit gives the appearance of such.  Actually the circuit turns one LED on and off.  When this one LED is on, the other LED is dimmed giving the appearance of being off.  The K-Line manual states such as I remember.  The Lionel manual clearly states the Red LED is turned on and off.  It doesn't say the green LED is turned on and off, just that it is illuminated.  So, if the Lionel LED dwarf operates like the K-line, the green LED will be dimmed (i.e. not off) when the red LED is illuminated.

Can you try running the insulated rail to a relay first. Perhaps someone can experiment putting a diode inside the signal to block the current in reverse directions. 

WftTrains posted:

As Train Nut posted above, the insulated rail by itself can automatically complete a circuit, in this case to turn on the red bulb (LED), but it can NOT OPEN a circuit to turn off the green bulb.  You need a relay*.  This has been discussed on here quite a bit.  Do a search for 153 Block signal wiring.

And do use auxiliary power, not track power.

Bill

* yes I know there is a way of doing it without a relay but as I recall it's much more  complicated than using a relay plus it really doesn't completely turn off the green light it just dims it.

 

My response above was obviously based on a #148 signal without a built-in relay as I also was not aware that Lionel ever made a 148 dwarf signal with a built-in relay.  It seems like there is not much room inside the housing of a 148 to add anything but with modern electronics I guess its possible. 

I looked up the current model of the 148 dwarf signal in the 2018 catalog and it has catalog number 6-12883.  I’ve got several different versions of the 148 installed on my layout including postwar, MPC and some more modern ones that were bought a few years ago.  Those most recent ones are also catalog #6-12883 based on the number printed on their boxes.  AFAIK they don’t have built-in relays as they came with 153C contactors in the boxes.  Plus the instruction sheets that came with them (sheet #71-2883-250 dated 7/04) state that you have to have a 153IR or a 153C to operate them. 

Therefore I’m confused - did Lionel add a relay to this accessory and NOT change the catalog number?  If so, when did that happen?  That’s a fairly significant change that should trigger a new catalog number. 

Also I see that Lionel still puts the red LED on the top rather than on the bottom.  I’ve reversed the bulbs on all of my block and dwarf signals to agree with the prototypical green-on-top railroad format rather than the red-on-top automobile street and highway format.   

Bill    

Okay. Now I'm confused. Lionel doesn't even show an LED version of this signal when i look up 148 dwarf. The current model they show is 6-12883 as wftttrains states.   Also the parts list does not show any kind of electronics inside.  Which my first thought would be it's just Lionel with another false statement in their catalog. But it does appear from the video above that the green light is trying to go out somehow.

Apparently Lionel did re-design the signal with LED's and didn't change the stock number. That wasn't the best idea. I'm guessing there is an electronic board in the signal that detects when a wheel is on the insulated rail and shunts the diodes. Maybe this is why no mention of a 153/153IR in the revised instructions, they would not work.

Chuck Sartor posted:

Apparently Lionel did re-design the signal with LED's and didn't change the stock number. That wasn't the best idea.

And unfortunately it looks to be another problematic, not thought out item/process...

Chuck Sartor posted:

Apparently Lionel did re-design the signal with LED's and didn't change the stock number. That wasn't the best idea. I'm guessing there is an electronic board in the signal that detects when a wheel is on the insulated rail and shunts the diodes. Maybe this is why no mention of a 153/153IR in the revised instructions, they would not work.

Chuck:

Thanks for confirming that as mine definitely are the older version of the 6-12883 with bulbs and no extra circuitry.

Bill

thanks to all of you who have commented on this - i have ordered a new signal - and i think i will open up the one that i tried to hook up and see if there are any special internals - it has the three wires not the four.  i do doubt that lionel put any sophisticated electronics in it for such a low price - will have to see when i get the new one to see if there is any difference.  

ted K posted:

thanks to all of you who have commented on this - i have ordered a new signal - and i think i will open up the one that i tried to hook up and see if there are any special internals - it has the three wires not the four.  i do doubt that lionel put any sophisticated electronics in it for such a low price - will have to see when i get the new one to see if there is any difference.  

I think you will find a small circuit inside the signal.  LED works on DC so there must be a rectifier to convert the AC to DC.    There can also be a simple circuit to illuminate the LEDs.

Apparently Lionel did re-design the signal with LED's and didn't change the stock number.

The stock number isn't 148 anyway.
How far down in the thread did the actual stock number appear?
It was something like 29 posts.

the number is 6-12883 - i tried the fast track activator section of track, wired the dwarf signal to aux power - green light came on, then i took an alligator clip from the outside insulated rail to the other outside rail between the isolators and the light turned red - removing the wire the light returned to green - no flickering - so it is the connection from the insulated rail to the other outside rail that is not effectively transferring through the truck on the car - will try cleaning the wheels and the track - but is seems that a "positive" connection between the outside rails is what is needed for it to work- also will try a longer heavy train to see if that helps

Might make the block a bit longer, then more wheels to make a positive circuit.

Ted   Again, FWIW, and to demonstrate Chuck’s point, here is the FT insulated section(darker grey ballast) followed by a 10” straight, signal, 10” straight.  The outside rail connectors on the underside of the straights have been(must be) removed.  And the track pin removed and gap increased with a dremel to assure no contact will occur on the last section.  This triggers properly, every time.

Chuck Sartor posted:

Might make the block a bit longer, then more wheels to make a positive circuit.

That’s why I suggested running the insulated rail through a relay first.