Transformer for model lights

[F2Andy]

I want to illuminate my layout, and I have realised the 12V output of my controller is not going to cut it. Is it reasonable (and safe) to use a transformer like this:

http://www.amazon.co.uk/60Va-Voltage-dimmable-Lighting-Transformer/dp/B0019ENKD0/ref=tag_stp_s2_edpp_url

It is designed for LV-Halogen lamps, rather than grain of wheat bulbs and LEDs, but would that be a problem? The output is 12 volt, which is what I want, and up to 60 W - enough for 100 grain of wheat bulbs rated at 50 mA. It is AC, as well, but that should not be a problem (no worries about putting in LEDs the wrong way around).

 

[Suzie]

It specifies a minimum load of 20VA which is 1.6A or 32 x 50mA bulbs which might be a problem if you do not want that many on as a minimum.

[kevinlms]

It specifies a minimum load of 20VA which is 1.6A or 32 x 50mA bulbs which might be a problem if you do not want that many on as a minimum.

Even if the OP had 32 lamps to light, he may not want them all to light at once. He may choose to light random groups of lights separately, using different switches, i.e. 4 groups of 8. If so, that transformer would be unsuitable. Better to use 2 or more lower powered power packs, IMO.

[F2Andy]

Ah, I had not noticed the minimum load. Okay, so would this one be good:

 

http://www.tlc-direct.co.uk/Products/LTYT105.html

[Suzie]

That looks better, but might be worth checking the voltage which does not appear to be specified!

[Stringfingerling]

Another reason for using a power pack - train set type - is being able to drop the voltage to taste, giving interesting light and longer life with grains of wheat.

Even if the OP had 32 lamps to light, he may not want them all to light at once. He may choose to light random groups of lights separately, using different switches, i.e. 4 groups of 8. If so, that transformer would be unsuitable. Better to use 2 or more lower powered power packs, IMO.

[jimikelly]

Hi there if you go on to youtube there is a guy telling you how to light up your layout by using a  power supply from a old  computer , hope this will help    . 

 

[Brian]

Hi
Exactly how many filament lamps are to be powered?

The main concern of using an ex computer PSU is the large amount of power (Amp) they can output. It's essential the output feeds are sub divided and each taken via some form of circuit protection. e.g. Use 1.0 Amp fuses or 1.0 Amp self resetting circuit breakers. These then provide each sub circuit suitable protection from possible short circuits which if the circuit was unprotected could cause wire damage and even a fire!

I personally would go with a regulated 12 volt dc PSU offering a lower output current than the ATX computer one.
A wall plug in PSU which has a 12 volt dc output at 2.0Amp or. 'Brick' type PSU would be ok to use. eBay is often a good source and at a reasonable price too.

Here are two examples...

http://www.ebay.co.uk/itm/2-Amp-CCTV-POWER-SUPPLY-12VOLT-PSU-High-Quality-CCTV-COLOUR-CAMERA/190586320487?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D14%26meid%3D8305618418136700847%26pid%3D100015%26prg%3D1006%26rk%3D1%26sd%3D190586320487%26

 

http://www.ebay.co.uk/itm/12V-12-VOLT-DC-DESKTOP-POWER-SUPPLY-PSU-4A-5A-5-AMP-AC-DC-/280910793879?pt=UK_ConsumerElectronics_PowerAdaptors_SM&hash=item4167968c97

Again I would sub divide the output into two or more sub circuits each with its own circuit protection device.

 

 

Edit to add eBay links