Garden Railway Forum

I need some help with those LED bulbs that are prewired please. I want to know if the members who are far more knowledgable about electrical things than I am. I have seen that if you look for them they always seem to be 12volt, isn't that too much to be putting through single bulb and wouldn't there be a a big battery holder needed to accommodate the voltage needed. I have used Jerry Irwin's lights in my recent build of his coaches and they only had two of those small round batteries or one if you don't want it to be has bright.

Am I right in thinking that 12 volts is the maximum that the bulb will take or is the something I am missing or for me I don't really understand....

Thanks for any reply which helps me with this silly question.

Hi Rod
When you say LED bulbs, do you mean the sort of bulbs which are put into car lights or the small individual LEDs which we use for our models? When you mention those in Jerry's coaches, I'm assuming you mean individual LEDs like these:
If so, you can put virtually any voltage through them above 3v (and some will take less than 3v) but they need to be protected with a current limiting resistor, which is what you get with pre-wired LEDs - the resistor is wired in. You can get pre-wired LEDs which will take less than 12v

https://www.ebay.co.uk/itm/194256368451

Or Phil at RC Trains will attach resistors to LEDs for you for any voltage.
https://www.rctrains.co.uk/Accessories.htm#LEDs

I hope that helps.

Rik

Hi Rod,
Rik got in first, but I slightly disagree with his wording..

If you buy a '12V LED bulb' it will have a 'something' to make it work with a 12V supply built into it. - The something may be a simple resistor, or something more sophisticated.

LED's have Forward voltage, which is different for different colours, and we can vary the brightness by changing the current through the LED.

In simple terms, the LED will always have the same voltage across it, but the current can be made different, by varying the value of the resistor in series.

It is a lot more complicated than that, but this simple approach works for our use.

Phil.P

Phil.P wrote: ↑Mon Aug 14, 2023 10:43 am Hi Rod,
Rik got in first, but I slightly disagree with his wording..

If you buy a '12V LED bulb' it will have a 'something' to make it work with a 12V supply built into it. - The something may be a simple resistor, or something more sophisticated.

LED's have Forward voltage, which is different for different colours, and we can vary the brightness by changing the current through the LED.

In simple terms, the LED will always have the same voltage across it, but the current can be made different, by varying the value of the resistor in series.

It is a lot more complicated than that, but this simple approach works for our use.

Phil.P

Yes, wot he sed .......

Rik

I can't offer any useful comment on the use of LED bulbs as it is all magic to me.. however, I note that Rod mentioned Jerry Irwin's coach interior light fittings as supplied with his kits and I know from experience that they are in strip form, so might be dealt with differently?

Peter Butler wrote: ↑Mon Aug 14, 2023 11:06 am I can't offer any useful comment on the use of LED bulbs as it is all magic to me.. however, I note that Rod mentioned Jerry Irwin's coach interior light fittings as supplied with his kits and I know from experience that they are in strip form, so might be dealt with differently?

Ah. Those led strip lights usually have resistors built in.
Here are some 3v strips. You can cut them to whatever length you want
https://www.layouts4u.net/flexible-led- ... -led-strip

Rik

Thank you so much for your kind information guys. That’s really very helpful.

Those strips look great Peter. I don’t suppose you know how easy it is to solder them to a switch do you. There isn’t any information apart from cutting to any length.

Sorry Rod, never tried soldering the strip lights as I don't use interior lighting in my coaches. There's probably everything you need to know on YouTube.

FWLR wrote: ↑Mon Aug 14, 2023 12:06 pm Thank you so much for your kind information guys. That’s really very helpful.

Those strips look great Peter. I don’t suppose you know how easy it is to solder them to a switch do you. There isn’t any information apart from cutting to any length.

If you are confident with a soldering iron, then you can solder directly to the strips..
If in doubt, buy the solderless connectors, which allow you to fit wire 'tails' to the strips, which you can then solder to your switch.

Phil.P

Thanks Peter. I will have a look on there. if those strips can be cut to length I was thinking they could be used for other things maybe, but then it could be just as easy to get the LED's for lights and things. I have used them for those yards lights I made for the turntable, so I know they are easy to do.

Thanks Phil. I have not to bad at soldering, but I have just bought some LED's from you, so I will stick with them for now, although I do like those strip lights that Jerry Irwin supplies with his coaches..

FWLR wrote: ↑Mon Aug 14, 2023 12:44 pm Thanks Phil. I have not to bad at soldering, but I have just bought some LED's from you, so I will stick with them for now, although I do like those strip lights that Jerry Irwin supplies with his coaches..

I did think it was a coincidence, with the name, but don't know you all on this Forum, as well as on one of the others..


We could do with 'bubble' floating above us at shows.. With our Forum-names, and avatars, on them. - It would make finding people so much easier!
Let's face it, 'older bloke, grey hair, glasses, covers a lot of us!

Phil.P

Phil.P wrote: ↑Tue Aug 15, 2023 9:54 am

FWLR wrote: ↑Mon Aug 14, 2023 12:44 pm Thanks Phil. I have not to bad at soldering, but I have just bought some LED's from you, so I will stick with them for now, although I do like those strip lights that Jerry Irwin supplies with his coaches..

I did think it was a coincidence, with the name, but don't know you all on this Forum, as well as on one of the others..


We could do with 'bubble' floating above us at shows.. With our Forum-names, and avatars, on them. - It would make finding people so much easier!
Let's face it, 'older bloke, grey hair, glasses, covers a lot of us!

Phil.P

You forgot bald and balding....I am hoping that Peter Butler of this parish can sort out a name tag he did a few years back for when we attend shows. He did, might have been someone he knows made an excellent one last time, but unfortunately I have misplaced it with moving a few times since.

Rod.. I have to apologise for not being able to find my own name tag to replicate, so we will need to devise some other way of identifying each other.

Thats ok Peter. I will have a think and let you know by email and then we can sort something out.

A Carnation in the buttonhole, and a bowler hat?

I'll get my coat..

Phil.P

Phil.P wrote: ↑Fri Aug 18, 2023 4:18 pm A Carnation in the buttonhole, and a bowler hat?

I'll get my coat..

Phil.P

More like a flat cap for us Northerners