I queried Bachmann and they do not produce plug-and-play signal lights of any kind for the N scale turnouts. It should be possible if the signal polarity of each of the three conductors exiting the switch can be determined. has anyone been successful in doing this? If so, is there a schematic to follow? I'm new to the group. Thanks
It would certainly be more realistic to set up signal lights on an N scale layout activated by the turnout switch. The Bachmann 16V DC Multi-Accessory Power Supply (Item No. 44219) providing power to the turnouts has the anode and the cathode clearly marked in red and black respectively. The power cord from the Power Supply to the slide-switch has no markings but it is simple to determine polarity with a multimeter.
This is where things get interesting. The output receptacle on the switch has three poles. In a normal analog configuration, one would expect the center pin to be the anode and the slider would reverse polarity to operate the switch. By noting the position of the switch which corresponds to the open position of the turnout, one would simply connect a green LED indicating that is the main-line.
Hence, one would think that by checking the voltage output in each pin, the anode would be identifiable. Interestingly, I was not able to get any current reading from connecting any combination of two pins. I changed the position of the slider (i.e. "direction") which is supposed to reverse polarity, and still nothing.
I then turned to the turnout itself to see if the three pole plug exiting the turnout is electrified. Well, it is not. I made sure the track was electrified when I checked. Moreover, the turnouts can be activated using the Multi-Accessory Power Supply even if the track is not electrified.
Is it possible the switch has some sort of logic circuit wherein the three wire turnout cable must be connected to the energized switch to "wake it up" in order for it to work?
I'm curious to see if there are any thoughts on the subject. Surely, I'm not the only N scale modeler that is trying to incorporate signal lights using the turnout switch do this.
If there is no way to do this, the alternative is to simply build a separate circuit with a three position toggle switch. In this case one must throw the turnout switch and the light switch separately.
the ones i had years ago, you slid the switch one way or the other then quickly pushed down and released the slider.
power only when pushed.
Willis.
As willis mentioned, the turnout control is designed to only apply power to the activating solinoid for a moment when depressed. Leaving power on for more than a moment results in burned out solinoid contacts. You'll need a latching relay, with it's own power supply for signal lights to control position indicator lights. The simplest way is with an Atlas #200 Snap-Relay.
Len
Thanks to Len and Willis for the info and advice. I had some time today so I decided to go the simpler route and use a DPDT on-off-on toggle to activate the dwarf signals I constructed. My choice is certainly not as elegant as having the turnout switch activate the signals but it's a reasonable compromise.......I was not trained as an electrical engineer but It should be possible to design a circuit with a microchip that activates the turnout solenoid for a millisecond and then stays on with the polarity of the leads changing with the position of the switch. This would certainly be worth the extra cost to have a plug and play set up.
Currently, the Atlas #200 Snap-Relay is probably the simplest way to do what you want.
Len