Train Order Signal wiring?

[Cajonpassfan]

Most generic USB chargers use switchiing-type power supplies (that produces filtered and regulated 5V DC) and they just cost few dollars each.  Most cell phones/smart phones from the last couple decades use those, so you might have one from an old phone lying around.  They usually supply 1A of current, which shoudl be more than you need.

Here is a 5V 2A one for $4 (plus shipping of course).  https://www.goldmine-elec-products.com/prodinfo.asp?number=G19740  Just cut the plug off, and hardwire it.

Thanks Pete, that link looks surprisingly like the adapter I posted, including the slide-off plug....?

[peteski]

Thanks Pete, that link looks surprisingly like the adapter I posted, including the slide-off plug....?

That's odd.  Did it originally have a USB plug on the end of the cord?  If you look at the specs on the unit does it show that the input voltage is 100-240V AC?

I don't have that specific charger, but I took couple of different ones I have and the open circuit voltage was  5.03V on one and 5.2V on the other.  If you have some other USB charger wall-warts hanging around, try them.

[Cajonpassfan]

Yes, it did have a USB plug

[peteski]

That is a switching power supply (the input voltage range confirms that). I'm surprised that is has such a high open-circuit output voltage.  I guess nothing is is written in stone.

Have you tried measuring the voltage with 1k resistor connected across the output?  That would put a 5mA load @ 5V.

[DKS]

Thank you, David, for taking the time. Wow, nice graphics and an interesting  approach. So the motor goes around in one direction only, at the cost of three micro switches and a three position rotary switch. Thanks for the links, too.
It’s certainly electrically simple, but the three position rotary switch turns me off, no pun. I’d really like the signal switch activated by the operator who is in another room to have just two positions: orders or no orders, blades up up or down. Center off would be okay, just to turn the power off when desired. That probably means the motor needs to reverse direction, and just two “end of run” micro switches?  Can the motor polarity be driven by diodes, ie the motor power is turned off by the micro switch, until reversed? I have a vague notion that might work...?
About your Note 2: 3V works, but the blades move really slow...that maybe okay...
Thanks again, Otto

OK, I wasn't aware that you never want to utilize the middle position. But even then, there's still no need to reverse the motor. Now you just need two microswitches, one at each end of the arm's travel, plus a SPDT toggle to control it. And the wiring becomes even simpler:



Note that you really don't need to "turn the power off" for any given signal--it's off as long as the signal is in the selected position, so a center-off toggle isn't necessary.

That is, unless you want to be able to control the LED for each signal individually--not sure why, but just in case you do, you'd need a DPDT center-off toggle, and this would be the wiring:

[DKS]

DKS uses this type of circuit in his animated models, but his write-ups in the animation section do not provide those kinds of details.

I'm happy to provide such details on request. Often I keep my descriptions relatively simple because there's never a single "right way" to do something--there are as many ways to accomplish the same task as there are modelers.

[Dirk Jan Blikkendaal]

Gentleman,

Thanks for all comments and help...... useful for me to!
I am the builder (www.atsfnscalemodels.com) and wiring/electrical solutions are not really my strongest point.

First some additional info. 
The LED is a white 0401 and is supposed to stay on all the time.
The motors are 2,5 rpm (depending on voltage of course) designed  for 3-6 V DC.
I have not been able to locate prototype info on the moving speed of the blades but 3V might be on the slow side.....
As stated in another reply, the turning direction of the motors is unimportant and reversing is not needed (but can be done).
My easy/cheap solution to operate the motors/blades was to add a simple pushbutton (1 button per motor and in 1 of the motor leads).
As long as you push the button the motor turns and the blade moves.
Given the slow movement, the long arc of the turning cycle (in both high and low position)and the rapid stopping movement of the motor when the button is released, you have ample time to stop the blade in the UP or DOWN position.
You only must have a good/clear view of the signal (mount the pushbuttons near the signal in the fascia or a nearby control panel).

I have thought about using microswitches but never really tried them...... will do shortly.
The given solution is very easy (THANKS A LOT) and is not very expensive to add.... involves only some extra installation time (and that I wanted to keep down).
But calibration of the signal movement might be easier to do........

One word of warning on installing microswitches on Otto's TO signal as it is set right now.....
If you install them now, the switch off point will/must be a little earlier than reaching top or bottom of the cycle.
That might matter for the horizontal position of the blade...... it might not be exactly horizontal yet; the down position is less critical (in my opinion). 
To solve this you have the move the little steel pin in the motor axle rocker arm a few mm's outward by drilling a new 0,5 mm hole.
That way the blade movement will be ABOVE horizontal and BELOW the present down position but by adjusting the position of the microswitches (they have 2 nice holes to adjust the fixed position) you can correct that.

Thinking about all this I will certainly try/test the microswitch option and probably adjust future signals.
Otto, let me know if you can intall your signal to your liking. If not, we will work something out.

Dirk Blikkendaal

[DKS]

Dirk, thank you for checking in! It's great to have feedback from a manufacturer. Regarding this:

I have not been able to locate prototype info on the moving speed of the blades but 3V might be on the slow side...

Many of these signals, which were typically located at a station, were operated by hand, so I do not believe speed is relevant. As long as the modeler takes the precaution to use the proper load resistor for the LED, a 5 VDC supply for both the LED and motors should be perfectly adequate.

As for the timing of the shutoff at each end of the cycle, a microswitch with a long lever can be located such that it does exactly what's required, and furthermore should be easily adjustable.

A pushbutton is a great way of controlling the signal, unless it is out of sight of the operator. This is why I devised the solution for Otto. I'm glad to know it may be of use to you as well.

[Cajonpassfan]

Thanks for the latest power schematic Dave, it doesn’t get much simpler than that (assuming I can attach the micro switches precisely).
Indeed, there is no need to reverse polarity as  the mechanism just goes around in circles. I used your first link to order the switches, so we’ll see. Agree about the manual operation; the two TO signals at Cajon and Summit were operated by manual linkages straight out the operator bay and so the speed of movement was very much dependent on the person working it. Apparently, it took a bit of muscle to move them...
It turns out my old multimeter had gone bad, so the readings I posted earlier were way off. I dug up another multimeter to double check and now get 5.15V DC output (with or without 1K Ohm load, Pete). That generates just about perfect speed for the signal blades.
As to the center off switch, that was meant to kill power to the LED’s when not running but having power on in the room to work etc. The wall wart is powered though a master kill switch which controls lights as well.

Dirk, thanks for your comments also. I’m not sure I want to mess with the mechanism though. The maximum TOP position seems just about perfectly horizontal as is; the BOTTOM position is a bit below 45 degrees where it ought to be. I’ll try to rig the switch so that it stops the movement at 45 degrees. Without reversing polarity, the blades will drop a bit before returning to horizontal. I can live with that.
Fun stuff,
Otto

[peteski]

. . .
It turns out my old multimeter had gone bad, so the readings I posted earlier were way off. I dug up another multimeter to double check and now get 5.15V DC output (with or without 1K Ohm load, Pete). That generates just about perfect speed for the signal blades.
As to the center off switch, that was meant to kill power to the LED’s when not running but having power on in the room to work etc. The wall wart is powered though a master kill switch which controls lights as well.
. . .
Otto

Ah, that makes more sense.  That wall-wart behaves more like what I expected.

As far as the LEDs go, the do not burn out like bulbs, so you can leave them on without worrying.  White LEDs do get dimmer as their on-time accumulates (the LED's phosphor's ability to convert blue light to yellow diminishes) , but we are talking about tens of thousands of hours to even notice slight change of brightness.  And when you are not running them at full brightness, the will last even longer.  I think it is safe to say that they will outlast you. 

[DKS]

Thanks for the latest power schematic Dave, it doesn’t get much simpler than that (assuming I can attach the micro switches precisely).

Precision isn't really necessary. Just get it in the ballpark, then bend the actuator until the unit behaves the way it should. Here's an ideal candidate:

https://www.ebay.com/itm/SPDT-MINI-SNAP-ACTION-LIMIT-SWITCH-W-LONG-FLAT-ACTUATOR-NOS-1-PCS/333275247441

[Cajonpassfan]

Thanks, Dave. I already ordered these...should be okay. [ Guests cannot view attachments ]

[Cajonpassfan]

Ha! BUMP! How time flies... and we are not getting any younger...
So I got another Train Order Signal form Dirk (Atsf N Scale), this one a two-position upper quadrant for Summit. Looks awesome!

To keep it simple, I'm using @DKS latest wiring diagram (see below), the only difference being a single 3V supply that powers both the motors and the LED's. It's slo-mo but I like if that way...these were worked manually by the local operator (see  Chard Walker at Summit, Cal., cca 1950, below. The TO signal hardware is on the right of the bay window.

So far so good. But, I'd like to be able to operate the signal both locally (on the Summit fascia) OR by the dispatcher (when we have one) from another room. How would I wire the dispatcher controls to override the local on/off switch? Keep it simple please..?
Thanks , Otto

[peteski]

This should work. Toggling either switch will change the position of the train order signal.  I represented the DPDT switch as it appears physically (not schematically) because it was easier.   

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[DKS]

Note that, in Peteski's diagram, the physical positions of the switch controls do not correspond to the signal aspect. The switches will change the aspect, but not show it. It's not possible for the switch controls to match the aspect when one control can override the other.