LED's and DCC

[Howie1632]

I've got a simple led with a rectifier hooked up to a sidind to indicate when it is powered.It's a blinking LED,but it don't blink while hooked to DCC and a rectifier but it does light up.When hooked to DC it Blinks just fine.What am i missing here¿ Thanks Harold

[BR60103]

I think that the AC component of the DCC power might have something to do with it. I've never had a blinking LED myself.

[woodone]

Not sure why your are using a rectifier with the LED. Unless you are using it to get DC voltage. Like Howie1632 said it is the AC voltage that is giving you problems.
The LED is only going to work if it is forward biased. The Anode lead must be more positive that the Cathode lead.
You could use a rectifer to get the AC voltage to DC. then that could operate your LED. You will need to use a resistor on the Anode lead also.
Some where in the 1K to 750 OHM range. The problem is that with DCC there will be AC voltage at all times on your siding, unless you install a switch.
So the siding is powered at all times with DCC, and your LED will be on too.
Question? Why do you need indication of the siding beeing powered?

[LynnB]

yep I agree , LED's work better if there being powered through dc power pack or stionary decoder or even off a tortoise switch ( for showing switch position ).

[Howie1632]

Woodone,the reason i want my sidings identified by blinking LED's is that my layout is Built over the doorways.I've got numerous sidings that i can barely see,so sometimes it gets a little confusing which siding is what.I found the fix eor what i want,which is a rectifier a capacitor and a resistor.With out the capacitor the LED won't blink,but with the Cap it works perfect.I could use a Decoder but if i reprogram something it could be affected.This setup works as i wanted it to. :

[woodone]

That is great!!
As long as it does the job for you. Do you have a switch to it also?

[fire5506]

The reason the LED won't flash is because it is being turned off and on before it would normally flash. Each time the voltage goes to zero the LED turns off. It has to stay turned on in order to flash. The rectifier and Capacitor smooth out the ripples so the LED does not turn off and it can flash.

Richard looking at MP 242 while working for the FEC Rwy.

[rrinker]

If you just want to see if the power is on or off on a siding, use a 2-lead bicolor LED and a 1K resistor. No worries about damage. It will be sort of a reddish-orange color.

--Randy