Converting a 4-4-0 LMS Compound Loco (R.376) with a Smoke unit to DCC

[Chrissaf]

Shane,

It would help to answer your question if you could state the Maplin Product Code for the item you have purchased.

 Hi Chris

The only numbers I have on the relay are  LU-12  3A 120VAC  3A  24VDC  I think it is made by RAYEXELEC

Shane 

 .

You said you purchased it from Maplin. Maplin have a letter / number product code on their packaging and web site pages. For example is it this one N15AW (link below)

http://www.maplin.co.uk/p/12v-dc-2a-spdt-sub-miniature-relay-n15aw

 .

If it is not this one, find the one you purchased on the Maplin web site and post the URL link to the exact product page.

.

The reason I need the exact relay info is that I need to know the coil resistance to calculate the relay operating draw current.

[shagey]

Hi

I would, opt for the relay control method. It saves the decoder from being overloaded on its function outputs.

Diode... Optional, but its use is to remove the Bemf produced as the relay de energises. The Bemf generated could cause decoder failure, hence a simple diode across the relays coil which costs a few pence will stop this. - 1N4001 etc  diode is fine.

Resistor.. Optional and really dependent upon your DCC rail voltage and the maximum rated working voltage of the smoke unit being used. Older factory fitted smoke units may well be able to operate at a voltage above the nominal 12 volts. DCC rail voltage in OO is typically around 14 - 15 volts.

 

Example of a micro 12v relay...

http://www.rapidonline.com/electronic-components/a12-wk-12v-dpdt-micro-relay-60-4032

 

 

Hi

Do you have a wireing  diagram    you could let me have  

I have just wired a relay up luck it has not done the decoder just the function 

Shane

 

 

 

Hi Again

just ordered relays  from your link thanks

Shane