I have mentioned this before, but have had little response. I used the automotive toggles on my old layout for sidings, but had a direct short if pickups spanned the rail gap with the switch off. I get continuity between the load and earth terminal with the switch off. I had a rocker like the second picture that showed no continuity between load and earth in the off position, so I ordered 15 of the ones pictured. Five show no continuity and ten do. My questions are: has anyone else had this problem and is there a way to solve the problem other than not connecting the earth terminal and having no light?
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Did you have the load(track center rail) connected to the center terminal?
I'm confused on your pictures. The small picture is too small to see what the switches are...they look like unlighted spdt toggle switches and would have a short from center to either side depending on which way they are switched.
The big picture shows lighted switches that probably have LOAD on the center terminal and SUPPLY and EARTH on the other two terminals. In that case, if they are LED, then the continuity from LED would depend on which multimeter leads are on which terminals because of the diode action of the LED.
If I am guessing right...
Corrected my switch leads...
The LED(and ground) should be on the side terminal, load on the center, supply on the other side.
And yes, switching the VOM leads from switch to switch will produce those results as reported.
Sorry about the small picture. They are SPST lighted, also, but probably incandescent. I am in the process of trying the led ones now by wiring a siding with the ground hooked to the top, load in the middle and supply on the bottom. How should the diode on the end of the switch earth wire be connected to the layout common?
I just went and checked with the VOM. Polarity of the leads makes no difference. The same five show no reading either way and the others show continuity either way. I will hook one to power and see what happens.
Sorry about the small picture. They are SPST lighted, also, but probably incandescent. I am in the process of trying the led ones now by wiring a siding with the ground hooked to the top, load in the middle and supply on the bottom. How should the diode on the end of the switch earth wire be connected to the layout common?
I just went and checked with the VOM. Polarity of the leads makes no difference. The same five show no reading either way and the others show continuity either way. I will hook one to power and see what happens.
Hmmm on the continuity so far...
Here's a schematic on the LED hookup.
Attachments
I wired one siding and got the same old result with a switch that I thought was ok. I didn't take time to put the diode on the earth wire, but I thought that was just to save the led anyway. With the siding switched off and the main powered, if you bridge the track gap I get a direct short to ground. If I could remember to never use an unpowered siding everything would be fine.
As these are simple SPST make-break switches, the only thing that should happen when you bridge the gap would power to the siding(through the pickups) and turning on the switch indicator light(through the center lead of the switch). The only "short" should be just enough current to light the indicator lamp, as that is the only route through the switch to ground/common.
Rob,
If you would email me, I will send you a couple of these so you can check them out. I could see the amp meter on the transformer jump to 5 amps when I shorted the gap with nothing on the track. It's always the backfeed that does it. I'm positive I have them hooked up correctly, but as my wife will point out, I've been wrong before. With the switch off, I get .2 ohms between center and outside rail.
Rob,
If you would email me, I will send you a couple of these so you can check them out. I could see the amp meter on the transformer jump to 5 amps when I shorted the gap with nothing on the track. It's always the backfeed that does it. I'm positive I have them hooked up correctly, but as my wife will point out, I've been wrong before. With the switch off, I get .2 ohms between center and outside rail.
What brand of switches are these?
I use the Calterm ones available at the auto store or auto section of the farm store.
They don't short across Load and Earth.
The rockers came from here. The toggles were local auto parts store. I even picked the US supplier for the rockers. I will see if I can find the Calterm ones somewhere. I have some extra switches if anyone is interested Thanks for the help
Here is the diagram of the switch:
There just doesn't seem to be any way to get 5 amps through the LED and current limiting resistor as depicted in the lower right drawing. I'll get you my address when I get home and have email capability.