April project questions and comments here please.

All your questions on the April project to go here please. 

Thanks, Robert. Small typo in the sub heading here as you have copied it from March, and not changed March to April.

Looking forward to this Geoff, will there be any logic diagrams as well ?

[user=465]Stubby47[/user] wrote:

Looking forward to this Geoff, will there be any logic diagrams as well ?

Not this time Stu - the brief is to keep it simple!!

Sorry about that Geoff. Must have been having one of my,,,oh what do they call them,,senior something or other. Never mind, it will come back to me.

Watching with interest here. 

So far Geoff, I am following you. I wonder how long that will last?  :hmm  

Wayne

Geoff, I seem to have loads of old transformers lying around, from things like Christmas decorations, razors, phone chargers and other things. These vary from 12v, down to 3.4v output.

Is it OK to use these for running LEDs, or are there problems with this idea quest:


 

Hi Jeff - they should be fine. I keep all of mine and have used several. Some provide an AC output, others DC. I will be showing how to allow for either when I post the details of wiring to a mains powered supply instead of the battery.

Geoff, you recommend a 1 Ohm resistor in the circuit.

Not knowing what a 1 Ohm resitor looked like (the colours, not the shape…) I found this website : Resistor Color Code Converter

I could not find anything in the YMR index.

Stu

That's a 1K (1000) ohm resistor Stu not 1 ohm.  Brown, black and red stripes I think.

Cheers
Dave

See ! See !!

Exactly my point….:oops:

Also brown, black, black, brown.

ive got some station ones to do so i will watch Geoffs progress

Brian

A very good explanation Geoff - thanks.:thumbs

Les

[user=52]henryparrot[/user] wrote:

ive got some station ones to do so i will watch Geoffs progress

Brian

Some station ones already done here but apparently not correctly as they seem to be a bit warm and trip the transformer after a minute or two.

[user=316]Gwiwer[/user] wrote:

Some station ones already done here but apparently not correctly as they seem to be a bit warm and trip the transformer after a minute or two.

That doesn't sound good, Rick. What type of station lights are they - bulbs or LEDs. Also when you say transformer, what have you actually got powering them?

Sorry for the delay in replying.

The platform lighting is unbranded but supplied in packs from an eBay seller "everydaygoodz".  They were advertised as and supplied in a bag marked 12vDC.  They have small rectangular lamp units which seem to emit the light from a glowing wire and are definitely not LEDs.

They are wired in parallel back to one of the cheap Hornby train-set type controllers which can be picked up for a few units of local currency quite readily.  The output is quoted as 12vDC.

The controller has a rotating dial which will regulate the speed of trains were it connected to the track but does not regulate the brightness of the lighting.   It is either on or off.  When it is on there is a faint but distinct smell of something being warm and after around 2 minutes the lights cut out.

They can be restarted but only by disconnecting the output and allowing the transformer to reset itself.  However because the lights remain warm when power is reconnected they will trip again in a few seconds.

Rick, if you have an Amp meter, connect that in series with the power supply & lights , in the 10Amp range - I suspect you are drawing far more current than what is available & the inbuilt protection in the power supply is activating.

Sol I don't have such a meter but have had the same thought myself.  Would there be any benefit in wiring the lights in series instead or is the total current draw the same either way?