I have powered both my 1121 and 1122 switches directly to a ZW transformer. When a car makes a bridge between the switch track with a fibre pin to the corresponding main line track, the switch buzzes. There is 15 volts between these two points and the solenoids “know that” and buzz away.
Since there is no controller connected to the 1122 switches but there is a controller on the 1121 switches and since both kinds of switch act identically, the lamp in the controller cannot be the cause of this buzzing.
Any thoughts about the possibility of silencing/cutting down this buzzing noise?
Nino from San Jose
Niño, I believe there is a way to power the switch with DC, or using a bridge rectifier that will cut the noise. I had learned this many years ago and don’t recall the specifics, but I think it is a relatively easy fix. Good luck, dennis
Nino,
The buzzing of the coils is normal, and happens exactly as you state due to the non-derailing feature of the switches. Powering the switch coils with DC will quiet them down.
Larry
It will also eliminate any warning that a coil is overheating, when you park a train on the turnout. You need to put a capacitive-discharge circuit between the DC power supply and the turnout. It can be very simple, just an electrolytic capacitor and an incandescent lamp.
Bob,
About a year ago, I converted my 1122 switches to fixed voltage. I didn’t use Lionel’s method of trying to grab the coil wires under the solenoid. I simply Dremeled a window into the bottom of my switches and added the jumper right there. Works great. I also added knife switches to cut the power to my two blocks of switches to eliminate buzzing if trains are parked on them. By the way…I discovered that this also eliminates the sudden stops that MTH engines do when passing over PW switches. Recently, I replaced my 027 switch controllers with 022 controllers and added a nice toggle setup to allow the lamps to show the proper position.
About a week ago, I decided to try and eliminate the solenoid buzz completely. I found one of your posts on a Forum and got the components and wired it up. It didn’t work. No matter what I seem to try, I’ve had no luck. I thought perhaps the components were bad and I swapped them out. I’m not getting enough power to either light the lamps (they stay VERY dim) and the switches won’t switch.My wiring setup for fixed voltage works fine, but as soon as I add the capacitor, resistor and diode…nothing. Do you have any ideas as to what the problem is and perhaps a solution for it? I’ve spent many days now on this and I’m stumped.
Thanks,
RogerNY
RogerNY - Welcome to trains.com! [C):-)]
If you just added the capacitor and lamp to your existing setup, then the problem probably is that you’re still using AC. You need to use a DC supply, returned to the outside rails (or a transformer terminal connected to them) and with its polarity matching the capacitors. For example, if the negative terminal of the power supply is connected to the outside rails, then the negative terminals of all the capacitors should also be connected to the outside rails…
If you did put in a DC supply, check to see whether the capacitor and supply polarities match.
Hi Bob,
Thanks for the response. I’m a bit confused, though. I do not have the thread about using a lamp and a capacitor. I am using the diode, resistor and capacitor. I’ve got my fixed voltage switches hooked to my ZW, although to test out the three components I also used a separate AC transformer. Do I need a DC transformer? I thought the diode changes the current to AC? Shoud I bag the three components I used and try something else? What’s the best way to do this? Thank you.
Roger
Bob, it may also be that Roger has it wired such that the lamp on the controller is a load on the capacitor in which case the lamp charging the capacitor and the lamp on the controller are acting as a voltage divider and the cap is never charging up to the necessary voltage to operate the switches.
Servoguy,
I think you may be on to something here. I’ve kind of suspected that the 022 controllers might be playing a role in this. I’m going to go downstairs and remove a bulb from it and see what happens. The strange thing is…the system works perfectly until I put those 3 components in…then nothing (or barely). I’ll get back to you on this. If that is indeed the case…smaller resistor? But I’m getting ahead of myself.
Roger
Nope…still no dice. However, something interesting…I took the wire to ground (to the switch ground terminal) off the cathode side of the capacitor and tried it on the other side. Pushed the switch controller lever and got a “click” but that’s it. Something is not quite right here.
Roger
Maybe you can detect the problem in my setup. Ordinarily, I have my fixed voltage switches connected to the B terminal on my ZW. But to test all this stuff, I’ve been using a separate small transformer. I have the + terminal of the trans. connected to the jumper coming off the switch. The common of the transformer I’ve got clipped to an outside rail. And everything works with that…switches work, controller bulbs light up. Now, when I add the diode, resistor and then capacitor to that circuit…nothing. ??
Here’s another alternative I want to run by you folks. What about using a separate DC transformer (instead of my AC ones)? Wouldn’t that eliminate the need for the diode, resistor and capacitor? Or would there be a problem with it mixing with the AC at the switch (ground terminal on the switch) where the controller wires come in?
Roger
Guys,
The problem IS the bulb. I played with my connections again and unscrewed the bulb. The switch “snapped” for the first time. Finally some progress. But…when I screwed the bulb back in, it was initially bright and within seconds it dimmed to almost off (and of course, the switch didn’t work anymore). So…I think we’ve found the problem. Now…as to a solution? I’m thinking that the resistor is too large for the switch AND a bulb (as Servoguy suggested). How do we calculate the size of the needed resistor? I kind of had a feeling about that last night and tried something extreme…I removed the resistor completely and then within seconds, there was a nasty smell. That was a microsecond before the diode exploded.
The two bulbs in the controller are 18V screw in. However, because of the mod I did on the controller, only one bulb is on at a time. Normally, as you know, 022 controllers with 027 switches will work the switch, but both bulbs stay on.
Roger
Roger, the resistor (or light bulb) that charges the capacitor does not supply enough current to light the the light bulb in the controller. That is the whole idea. The resistor limits the current through the coils to keep them from emitting smoke. If you changed the resistor so that the capacitor voltage stays high enough to light the bulb in the controller, it would also be high enough to smoke the coils.
Exactly right.
I think you found an old post describing an early version of my circuit. If you use a number-53 lamp instead of the resistor and power the whole thing with a DC supply, it will work much better, with a much faster recharge, while still protecting the turnout.
Bob,
Just as I thought…the bulb. So, let me get this straight then…you suggest that I keep the diode, put it in line with a #53 bulb and then the capacitor, but instead of my ZW for power, use a DC transformer? Is that all correct? And I have one more question if it is…if I’m going to power the switches and controller bulbs from a DC transformer, why the need for the diode, lamp and capacitor?
You folks are being real helpful and I appreciate it. Thanks!
What is the link to the post that includes the bulb as a substitute for the resistor?
Roger
No need for the diode with a DC supply. Connect the negative terminal of the DC supply and the negative terminal of the capacitor to the outside rails. Connect the positive terminal of the DC supply to one terminal of the lamp. Connect the other terminal of the lamp to the positive terminal of the capacitor and to the common of the solenoids.
If you want to make your own DC supply from the ZW, connect the anode of the diode (1 ampere, 50 volts minimum, a 1N4001 for example) to a ZW output terminal. Connect the cathode of the diode (the end with a ring painted around it) to the positive terminal of another electrolytic capacitor (2200 microfarads, 16 volts minimum) and to the lamps of all the capacitive-discharge circuits you have. Connect the negative terminal of the capacitor to the outside rails.
You might want to read this recent topic: http://cs.trains.com/TRCCS/forums/t/202264.aspx
Hi Bob,
But here’s the crux of the problem…I replaced the 1122 controllers because they have a silly design and you really can’t see the bulb colors. Then I had to modify my 022 controllers with a toggle and DPDT switch so I could show just green or just red (to correspond with switch position). And it all works great. So…if this buzz fix doesn’t allow power to the controller bulbs, it’s for naught. I have to figure out a way to to provide separate power to those controller lamps so they’ll still get power and …work with my toggles.
Thanks!
-Roger
The only way I can see it working with your present scheme is to put smaller lamps into the 022C, such as number 52s, and then use a larger lamp, like a number 57, to charge the capacitor. This would keep the steady-state current through the coils about the same as it is now, which is safe. You would probably have to color the 52s yourself and they wouldn’t quite fill up the holes in the 022C (G-3.5 versus G-4.5).
Otherwise, you could modify the 022Cs for separate power to the lamps.
Bob,
Well, I had some success earler this afternoon. I have 4 wires coming off my DPDT toggles to the lamps. One wire connects to the side of a lamp, the other to the contact pt. to the nearest switch wire. I had cut a slit in the connection between the lamps and the rest of the switch controller. That’s why my toggles can work the lamps. I have MPC and modern controllers with jewel caps so I don’t have to worry about bulb color (my parts guy provided me with caps that are color matched). Anyway…this afternoon, I removed one lamp wire each…the one that connects to the switch wire contact pt inside the controller. I then clipped one wire each from the contact points of my open knife switches and connected each to the open lamp wires. Bingo! My toggle works the lamps and the capacitor, diode, resistor is switching the switch. Very cool. When I clean it up ( and make sure it’s REALLY working) I won’t hook to the knife switches…that was just a convenient short wire’s length. I’ll probably create terminal blocks from the ZW output I use for this. So far, so good. Finally some progress. Seeing the switch swivel and the lamps lighting WITHOUT buzz is pretty exciting.
You and Servoguy have been real helpful. I may yet be back to you, but so far, I’m liking what I’m seeing (and not hearing).
Roger