Lights for Bachmann Baguley Drewry

[Peter Richardson]

I have just purchased a Bachmann Baguley Drewry diesel and am interested in fitting lights. Has anyone had a go at this who could provide advice on type of resistors required and suitable LEDs?

Thanks

Peter

[Graeme Dunbar]

This sounds like a job for the Electronics SIG. :-)

There are online LED resistor calculators such as this one.

LED resistor calculator

White LEDs have a forward voltage of about 3 V or a bit more. How much current will depend on the LED and how bright you want it. Often the typical current values for LEDs is too bright for model railway use. 5 mA may be ample. Operating voltage is another matter. Nominally model railway motors are 12 V maximum. , but not many controllers put out a constant voltage for a given throttle setting. Many are pulsed and give out peaks considerably higher. Also pulsed supplies make LEDs look brighter than ones powered by supplies that have a constant supply of equivalent average voltage.

You can probably start with the assumption of 12 V even if you rarely if ever drive at maximum speed.

That suggests starting with a resistor of about 1 k and see how it goes.

There are surface mount LEDs that are available pre-wired in a variety of sizes, e.g.

pre-wired LEDs

[Peter Richardson]

Thanks for this advice Graeme!

[Alec Hudson]

On DCC I use surface mounted leds with a 47k resistor.