Resistance for Detail West ditch lights DL-228, 1.5 V

[SD40-2W]

Hi Guys,

I am operating on regular DC with an MRC power pack.

I would like to know what resistance you would use with Detail West ditch lights (DL-228) 1.5 V bulbs ?

Thanks for your knowledge and assistance,

 Michel D.

[modelalaska]

 Are you sure those are 1.5 volts?  The ones in my kit (DL-3 something) were 3.0 volts.  If they are 1.5, then 750 ohm to a 1,000 ohm should work fine.

Peter

[SD40-2W]

1.5 V is what is written on the product packaging for DL-228. 

Thanks Peter, that's much appreciated.

 Michel D.

[jasperofzeal]

It would probably be easier for you to use a constant light circuit like this one.  Before I got into DCC, I used to use this easy to solder kit by Utah Pacific.  The link to the circuit I gave you at the begining is very similar to the Utah Pacific item, so if you do it yourself, it would be cheaper.  Other manufacturers make ready-made constant light circuits for DC use.

[rrinker]

 Second Tony's suggestion. The drop across 2 diodes is 1.2 - 1.4 volts which will be just right with the 1.5v bulbs. The bulbs would see that voltage from the time the throttle got to 1.2 volts all the way to maximum. With a resistor, the voltage across the bulb will vary dependign on how fast you're going, and a resistor that makes the bulbs look good at slow to medium speed could very well allow more than 1.5 volts through at full throttle.

                          --Randy

 

[SD40-2W]

Thanks Tony and Randy.

 Michel D.

[modelmaker51]

It would be safer for the bulbs to use a constant intensity light circuit such as this one:

 

You can get the diodes at Radio Scack. Keep the silver band in the same orientations as shown above. The ditch lights would be hooked up in parrallel with the forward light.

[SD40-2W]

modelmaker51

I've got it,

Thanks

Michel D. 

 

 

[SD40-2W]

Hi jay,

I made an exact copy of your constant lighting  set up  based on your photo arrangement.

It did work well with a 1.5 V incandescent bulb until too much heat melted the whole sheebang. The 1.5 bulb was saved.

I guest I made an error !

Any idea about this heat ?

 Thanks.

 Michel D.

[rrinker]

 What melted, the diodes? What sort did you use, the little ones in glass cases or slightly larger ones in black epoxy? You didn;t hook it up across the track, did you? I needs to go through the motor.

                                 --Randy

[SD40-2W]

Hi Randy,

I used a black with silver stripe diode 1N 4007 bought at the local electronics store many years ago. I have used these on many occasions to make directional lighting with 12 V bulbs.

Note that I am not using  Detail West 1.5 V ditch lights DL-228 at this time but 1.5 V the Miniatronics one's.

It melted while being hooked up across the track but it also heated up much while testing on the MP power pack.

What do you think ?

Michel D.

 

[richg1998]

 The circuit DOES NOT go accroos the track or power pack. You cut one wire going to the motor and insert the circuit in SERIES with the motor lead.

http://www.mrollins.com/constant1.html

http://home.cogeco.ca/~rpaisley4/xConstLight.html

http://www.awrr.com/ConstantLighting.html

Rich 

[SD40-2W]

Thanks Randy and Rich.

MD