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I am looking at using the Atlas Relay Switch (200) to power red and green trackside lamps. I will be using similar lamps to mount on the control panel.
I am using the small standard transformer with AC and DC connections.
I need the lamps on the AC side, non-resistors.
Any ideas on getting the lights from a vendor.
What type, size, voltage lamps with long leads can I use?
Where can I get them?
You need 12-14 volt incandescent grain-of-wheat bulbs in the appropriate colors. Model Power used to sell them, as well as clear, but that was a number of years ago. Try e-bay. LHS might still have them. As far as the length of the leads is concerned, you probably get 6-8 inch leads, and if necessary solder longer wires to them, insulating the joints with heat-shrink tubing.
I am looking at using the Atlas Relay Switch (200) to power red and green trackside lamps. I will be using similar lamps to mount on the control panel. I am using the small standard transformer with AC and DC connections.
I need the lamps on the AC side, non-resistors.
Any ideas on getting the lights from a vendor.
What type, size, voltage lamps with long leads can I use?
Where can I get them?
I believe the trackside lamp fixtures use what is called a "grain of wheat bulb". I did searches on-line for things like "green, grain of wheat bulb". I got lots of hits on ebay, and amazon, various hobby stores, and electronic supply places.
I would look for bulbs that can take 16V as most transformers put out 15VAC.
You might be better going with LED lamps. With LED's , you have to use a DC supply and the proper polarity is required. A small "wall wart" supply would easily work . Your atlas relays can easily switch the power for the LED's. You could also get a AC-DC converter and connect it to your AC terminals of your transformer. LED's require a resistor , but you can place it anywhere in the line. By experimenting with different values of resistors , the intensity of the LED can be varied. If you want to get fancy , they make small dimmers for LED's.
As for finding small "grain of wheat lamps " , they are getting much harder to find. I've seen a few in my hobby shop , but they are only clear and not very cheap.
um .. don't need a DC supply as LED's are a diode. If using AC and depending on the LED polarity, they conduct during the positive cycle ( LED on ), they do not conduct during the negative cycle. Dropping resistors are still required; think 20mA for the LED for maximum brightness. Always check the data sheet to see what current they can do Forward then adjust your resistor accordingly to the brightness you wish AND make sure that your reverse voltage is less than the LED's requirement.
um .. don't need a DC supply as LED's are a diode. If using AC and depending on the LED polarity, they conduct during the positive cycle ( LED on ), they do not conduct during the negative cycle. Dropping resistors are still required; think 20mA for the LED for maximum brightness. Always check the data sheet to see what current they can do Forward then adjust your resistor accordingly to the brightness you wish AND make sure that your reverse voltage is less than the LED's requirement.
True , but most LED's have a low PIV (max reverse voltage) around 5 volts or so and they may be damaged if this voltage is exceeded , which would happen when using AC above 5 volts. The exception is 2 lead bi color LED's .
