G Scale Model Train Forum banner
1 - 3 of 3 Posts

·
Premium Member
Joined
·
191 Posts
Discussion Starter · #1 ·
Hi Guys,

I am in the middle of battery powering my Bachmann Railtruck. I have decided to scrap the Bachmann circuit board and so will need to protect the led headlights and tailight. I know I need to reduce the voltage to the Leds but have no idea what to use or what size. Resistor? Diode? Do I wire all three in series or parrallel?

There was some kind of LED primer posted but searching on Led just doesn't work. Any help from you electronics experts will be appreciated!!
 

·
Premium Member
Joined
·
191 Posts
Discussion Starter · #5 ·
Del,
The voltage in the battery when fullly charged is !5.3, Nominal voltage is 14.4. The calculators Greg refers to are great but I have no idea what the headlight voltages are or the voltage of the taillight. Because of this I cannot use the calculator. I have the wiring diagram but it includes no information helpful in this situation. When I am done with the installation I want all lights on both in forward and reverse, so I am still stuck. I was planning to connect the output of my receiver to a resistor or diode then to the three positive leads of the leds, with the negative leads connected to the headlight screw on my receiver with a jumper over to my Rearlight screw. This I figured would allow all three leds to be on regardless of wether I was going forward or reverse.

Greg If I understand your simple method and my voltage is 15.3, I would need a 300 ohm resistor. Is that correct.

Does the resistor always get connected to the positive lead on the led or does it matter??
 

·
Premium Member
Joined
·
191 Posts
Discussion Starter · #11 ·
Thanks to all for the great info!! George I do believe it was your primer. Greg, Your references were very helpful.
 
1 - 3 of 3 Posts
Top