I found a 12v flashing LED at Frys last night. It says it needs no resistor and operates off 12v. I hooked it to the accessory terminals of my CW-80 that I programed to 12v, the light works but it does not flash. Any suggestions?
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0-18V AC programmable accessory output?
LED likely runs off of 12V DC. You need to build a little rectifier circuit.
Regards,
LED likely runs off of 12V DC. You need to build a little rectifier circuit.
Regards,
Try a 9V battery, it should flash on stright DC.
Just a rectifier will not work, a filter capacitor
is also required.
Just a rectifier will not work, a filter capacitor
is also required.
quote:Originally posted by CJ Meyers:
0-18V AC programmable accessory output?
Regards,
Yeah the CW-80s (revised version) If you hold down the Direction, Whistle and Bell Buttons, you can custom set the output voltage on the accessory terminal to anything between 0-18 VAC with the handle.
So I need a filter capacitor and a rectifier to make this work on AC?
Anyone willing to volunteer a parts list? 
quote:Originally posted by TMack:
Anyone willing to volunteer a parts list?
The link shows a simple diagram for a rectifier bridge.
Andre.
Use any bridge rectifier 1 amp or more,50 volts or more. Or use a dedicated DC circuit made with a larger bridge so individual rectifiers are not needed. LEDs will work on AC but the reverse voltage may shorten their life.
Here is a simple LED circuit with a small bridge pictured.
http://www.jcstudiosinc.com/Bl...d=619&categoryId=426
Dale H
Here is a simple LED circuit with a small bridge pictured.
http://www.jcstudiosinc.com/Bl...d=619&categoryId=426
Dale H
The absolute maximum reverse voltage of most LED's range from 5 to 7 volts. I suggest that not using DC on them will most certainly shorten their life, sometimes to minutes or hours! I had some failing regularly in one locomotive until I realized that I had the proper resistor, but no diode!
Don't run LED's on AC, a major factor in choosing LED's is you should never have to replace them. That's not true on AC.
Don't run LED's on AC, a major factor in choosing LED's is you should never have to replace them. That's not true on AC.
Flashing LEDs require DC to flash. Using anything but DC will reset
the timing circuit inside the LED before it times out so the LED
will not flash. A rectifier and a filter capacitor are required.
Using just a rectifier will reset the flashing circuit so the
capacitor is required.
the timing circuit inside the LED before it times out so the LED
will not flash. A rectifier and a filter capacitor are required.
Using just a rectifier will reset the flashing circuit so the
capacitor is required.
quote:Originally posted by TMack:
Anyone willing to volunteer a parts list?
If your flasher from Fry’s is as shown, I suggest these Radio Shack items. Fry’s might carry equivalent in-store. I selected a capacitor that lets you add a 2nd flasher by simply connecting to the 1st, red-to-red, black-to-black.
1N4001 diode (you get 2, only need 1)
470uF 35V electrolytic capacitor
If you run DCS, you might want to add a 100uh choke in there to avoid causing problems with the signal.
