LED's

[ohanlonmartin]

I need leds for my track display point control and for fitting inside Metcalfe buildings, a friend suggested using AliExpress in China and I have searched their website which has lots of options,  some of which have wire leads attached to the led which I think makes life easier, for me anyway.

 

Preferably I would like to use 2mm or at least no bigger than 3 mm, there are 50 points to be operated and lit on the track plan display, I am using the stud and probe method with Seep point motors.

 

Can I use 12 volt leds without the need for resistors on each led?

 

How many individual leds (sited within buildings) can I have constantly lit from a 15 volt transformer?

 

Has anyone any experience of AliExpress and their safety/reliability?

[Suzie]

Buying from AliExpress you don't really know what you are getting, unless you have a recommendation for a seller.

 

Since you have Seep motors you will need the type with the switch, and not be using it for frog switching unless you are using DCC.

 

LEDs will need resistors in series with each appropriate to the voltage they are being run on.

 

The number of LEDs you can have will depend on the rating of your transformer. If running LEDs from AC you will need to use them in pairs connected in inverse parallel.

[Mike Storey]

Surely you would be better off buying the leds which come in ribbon strips, pre-wired in effect, and include a resistor for every three or so? Firms like TrainTech and similar seem to be offering these at reasonable prices in bulk.

[Memphis32]

The ribbons would do for buildings, but won't work so well for point indication

[njee20]

Buying from AliExpress you don't really know what you are getting, unless you have a recommendation for a seller.

 

To be fair, unless you're buying Kingbright from Farnell or something you don't really know, and buying a bulk order of 'bog standard' LEDs I'd suggest AliExpress to be just fine. Indeed I buy all my little electronic bits from China, and they've all been faultless.

 

I'd be less keen buying anything with a mains charger, mind.

[Mike Storey]

The ribbons would do for buildings, but won't work so well for point indication

 

Perhaps some confusion here. The ribbons, as opposed to rigid strips of LEDs, are not meant to be used together. You cut off one or more from the strip for each occasion you need one. The ratio of one resistor to every three LEDs is due to the makers expecting them to be used for purposes other than model railways, so you need to add resistors when used singly, but the LED is pre-wired on copper strips, which makes connection relatively easy compared to buying single LEDs.

[gismorail]

Something that was debated ages ago was the use of Led Christmas tree lights which come with a plug in transformer and its just a matter of extending the wire between the lights to suit the layout situation . Shops are still selling off stocks from Christmas at very cheap prices currently

[ohanlonmartin]

Thanks for all replies to date,

 

Should have clarified that I am using DCC, I am aware or the led strips but with my (very) limited knowledge of electrics the idea of a single led bulb unit is appealing and of course that's what's needed for the layout control panel, the leds on offer with the wire leads attached are handy - for me anyway.

 

My son buys some stuff from AliExpress and seems to have had very little trouble except of course that there can be a lengthy wait on delivery.

 

It occurs to me that while buying from the regular suppliers in the UK would be negligible risk security wise but where do those UK suppliers source their merchandise from?

 

My misgivings are around the risk of the items actually being received and not incurring a total loss of money on the order, perhaps I will get my son to use his account for my order as he is an established buyer with them.

 

In reality the cost of the items are so low, including free shipping, that even if it is a disaster I would not be out of pocket by a huge amount.