model-trains Posted July 28, 2016 Share Posted July 28, 2016 I have included lighting over my Railway Inn signs these lights have shades and are suitable for, illuminating signage, buildings and yards etc. They are from Kytes Lights and are just £7.50 for 6. They are called white Light Shades. They are 6 volt but are supplied with resisters to make them 12 volt. Alternatively two can be linked together to make 12 volt equivalent, the problem with that method is that if one bulb blows they both go out. I have included resisters on all 4 lights and will be linking to one switch. More in this later. The first image is using flash on the camera, the Railway Inn we go in the far corner, it is currently positioned for testing. The second image is without using the camera flash so as to show the lights better. My lighting is on its own lighting bus, and is powered by a separate transformer. I started to build a new layout earlier this year, please feel free to browse the images in the Gallery link below. Thank you for viewing. http://www.rmweb.co.uk/community/index.php?/gallery/member/21331-model-trains/ Link to post Share on other sites More sharing options...
HLT 0109 Posted July 28, 2016 Share Posted July 28, 2016 I see from your blog that you have made extensive use of lights from Kytes Lights - so have I - and I am familiar with the shaded lamps on your Railway Inn. I have used a set of six on the outside of my loco shed. I think Joe Kyte's products are excellent value for money but, if you use a lot of the grain of rice/wheat bulbs (as I have done) you can easily exceed the capacity of your power supply and, more importantly, the current rating of the wiring (as I did!). Fortunately, the thermal cutout saved the day. Well done with the layout - you are clearly having a lot of fun with it. Harold. Link to post Share on other sites More sharing options...
cliff park Posted July 28, 2016 Share Posted July 28, 2016 It's a good idea, especially with 'scenic' lighting. to under run conventional bulbs. A 12v bulb fed with 10v will last almost forever, and it looks a more natural light. The long life aspect is a particular advantage if buildings have to be dismantled to change a bulb. It might work to put 3 of the 6v bulbs in series across a 12v supply. They might be a bit dim though. Link to post Share on other sites More sharing options...
model-trains Posted July 30, 2016 Author Share Posted July 30, 2016 Hi Harold, thanks for your reply. I agree Kytes Lights are good value and there is a lot of choice. Joe is also very helpful, I hadn't a clue when I started out with the lights and he answered every question I had in a very helpful way. I will add another update below shortly. Link to post Share on other sites More sharing options...
model-trains Posted July 30, 2016 Author Share Posted July 30, 2016 Hi Cliff, thanks for your comments. Why not link three bulbs and see if they are bright enough. I agree having to dismantle something can be not just a pain but can cause damage to what we have spend ages making. The lights on the hotel slot into the cardboard and the wires come out of the back of the Inn so if I have to change later it shouldn't be a big issue. It is worth thinking ahead... I think Link to post Share on other sites More sharing options...
model-trains Posted July 30, 2016 Author Share Posted July 30, 2016 I have included another 4 images in the Gallery today having now got the switch boxes in place. At present power is to one switch box and when I wire in both with be fed from the one. Wiring will be linked up so that if ever I have to split them into two halves it should be easy to do. I have also left myself space to add another power supply to the second box if I do chose to split them and also room to add more switches. Early days as you can see, lots to do (as well as playing trains) Here is one of them, the Railway Inn in place, tarmac to be resurfaced first and cars added into car park, two will have lights that work from the various switches. Link to post Share on other sites More sharing options...
DCB Posted July 30, 2016 Share Posted July 30, 2016 Most model railway 12 volt power supplies are around 18 volts off load so maybe tripling up with 3X 6 volt bulbs in series could save a lot of watts being wasted as heat from resistors. (I don't like resistors, especially in card buildings.) Link to post Share on other sites More sharing options...
Gordon H Posted July 31, 2016 Share Posted July 31, 2016 (I don't like resistors, especially in card buildings.) Yes, that had been noticed ... Other than better use of the power, how is a hot bulb any different from a resistor in a card building if the same number of Watts is being dissipated overall? Link to post Share on other sites More sharing options...
model-trains Posted July 31, 2016 Author Share Posted July 31, 2016 Good point. I found most LED's don't get hot, but the resistors can burn your fingers if not careful. I was going to sleeve the resistors in shrink tubing but only had the very narrow tubing. So I put insulation tape on the card at the back of the building then insulation tape around each resistor and solder points. Link to post Share on other sites More sharing options...
DCB Posted July 31, 2016 Share Posted July 31, 2016 Yes, that had been noticed ... Other than better use of the power, how is a hot bulb any different from a resistor in a card building if the same number of Watts is being dissipated overall? Generally bulbs are placed in open areas with reasonable air flow, resistors are all too frequently poked into confined spaces or even taped to card walls with masking tape... Link to post Share on other sites More sharing options...
28XX Posted July 31, 2016 Share Posted July 31, 2016 So the generally applicable advice is: Without doing detailed calculations or extensive stress testing, filament bulbs are fine in card buildings with due regard to some airflow, but never leave them unattended and arrange all your power supplies at whatever voltage or current to be easily switched off at the end of every running or modelling session. Link to post Share on other sites More sharing options...
28XX Posted July 31, 2016 Share Posted July 31, 2016 Deleted Link to post Share on other sites More sharing options...
Gordon H Posted August 1, 2016 Share Posted August 1, 2016 Generally bulbs are placed in open areas with reasonable air flow, resistors are all too frequently poked into confined spaces or even taped to card walls with masking tape... How do you get any noticeable airflow in an enclosed card building? Do you always construct them with at least two windows open? A resistor should be chosen for not only its main feature of resistance, but also its power dissipation, taking into account its physical size and consequent temperature rise. In some cases you would apparently only 'need', say, a 1/4W, but might choose to fit a 1W to ensure its temperature remains sensible. People who choose to tape hot devices to card walls ought to know better, and probably soon will. Link to post Share on other sites More sharing options...
model-trains Posted August 1, 2016 Author Share Posted August 1, 2016 I find I can touch the LED bulbs no problem with getting to hot. When I tested the lights before fitting I touched one wire to the volt control and held the resistor to the other, in less than a minute I found I couldn't hold the resistor wire it was so hot. Realistically it is doubtful we would have these lights on on the time, I think. But resistors need to be well insulated, not directly onto card, or shrink tubing around them. Good advise from 28XX... never leave unattended I have provided power, first to a switched fused spur, then to an extension lead fixed to the upright of a support leg. One switch can switch everything off. I did this because I found myself forgetting I had left power on. Link to post Share on other sites More sharing options...
Gordon H Posted August 1, 2016 Share Posted August 1, 2016 I find I can touch the LED bulbs no problem with getting to hot. When I tested the lights before fitting I touched one wire to the volt control and held the resistor to the other, in less than a minute I found I couldn't hold the resistor wire it was so hot. Realistically it is doubtful we would have these lights on on the time, I think. But resistors need to be well insulated, not directly onto card, or shrink tubing around them. The reason your LEDs do not get hot is because they are not dissipating much power. Assuming they pass 20mA, which is a bit high for today's efficient LEDs, and with a typical 2V Vf, that only comes to 0.04W. Using a 12V supply, that means the resistor is dropping the remainder, i.e. 10V. So, dropping 10V @20mA, that means a resistor of about 500 Ohms, which will dissipate 0.2W. So, a 0.25W resistor would be running at 80% of its capacity and getting quite hot as a result. Use, say, a 2W resistor instead and it will be running at only 10% of its capacity and due to its considerably larger surface area, will run a lot cooler. A more efficient solution would be to use more LEDs in series in the first place, say three, with a total Vf of 6V. To drop the remaining 6V @20mA, you would use a 300 Ohm resistor which would dissipate only 0.12W, so in theory you could use a 0.125W resistor, running virtually at its limit - but again this would be better as a 0.5W resistor to keep its temperature down. By having three LEDs instead of just one, you get a lot more light to start with, so can reduce the current considerably, so the dissipation figures will get even better. The thing you shouldn't really do is encapsulate a resistor in sleeving, as this prevents it from dissipating the power it is producing, leading to excessive temperature in the device. Better to design the circuit to do the job properly in the first place than compromise on reliability and safety for the sake of a few extra pence. Link to post Share on other sites More sharing options...
model-trains Posted August 1, 2016 Author Share Posted August 1, 2016 There are probably be of few of us out there that do not know these things. We are constantly learning, for me it was not trying to save a few pence, just trying to apply logic to something I found but was not aware of. My thoughts were down to instinct, if the resister gets hot protect it from the card. Would I be therefore better, based on what you have said, to remove the insulation tape from the resistor/wire completely but instead add a small piece of something between the resistor and the card that will not be affected by the heat from the resistor but also stop the heated resistor coming in contact with the card? The resistors are on the back of the Railway Inn, but also up against the up-stand so maybe I should try get a bit of hair round it, I mean air round it, keeping it maybe 6mm from the up-stand. Lighting for me is an addition to the layout I can control for small periods as I wish, I do not plan long periods where lights would be on and I have safe guarded myself with the fused spur isolating switch that knocks everything off when unattended. Thanks for your help Gordon H Link to post Share on other sites More sharing options...
model-trains Posted August 1, 2016 Author Share Posted August 1, 2016 I guess the best option then is, if using a 12 volt system try keep lighting to 12 volt LED's and not use resistors. Fortunately, all my station lights, street lights, cars lights and burger bar are all 12 volt. The Railway Inn was the only 6 volt lights with resistors are those used to light the signs, they were purchased to suit the need; suitable lights with shades. Knowing what I know now I would have left off the resistors and connected two lights together to the one switch. Could I have wired to lights together back to the one switch and done the same with the other two lights but, taken both back to the same switch? I guess the best option then is, if using a 12 volt system try keep lighting to 12 volt LED's and not use resistors. Fortunately, all my station lights, street lights, cars lights and burger bar are all 12 volt. The Railway Inn was the only 6 volt lights with resistors are those used to light the signs, they were purchased to suit the need; suitable lights with shades. Knowing what I know now I would have left off the resistors and connected two lights together to the one switch. Could I have wired to lights together back to the one switch and done the same with the other two lights but, taken both back to the same switch? Link to post Share on other sites More sharing options...
Gordon H Posted August 2, 2016 Share Posted August 2, 2016 A '12V' LED simply has a resistor built in, so could get quite hot in the same way a bulb does for the same current. Unfortunately, the excess power still has to go somewhere. Link to post Share on other sites More sharing options...
RMweb Premium kevinlms Posted August 2, 2016 RMweb Premium Share Posted August 2, 2016 I guess the best option then is, if using a 12 volt system try keep lighting to 12 volt LED's and not use resistors. Fortunately, all my station lights, street lights, cars lights and burger bar are all 12 volt. The Railway Inn was the only 6 volt lights with resistors are those used to light the signs, they were purchased to suit the need; suitable lights with shades. Knowing what I know now I would have left off the resistors and connected two lights together to the one switch. Could I have wired to lights together back to the one switch and done the same with the other two lights but, taken both back to the same switch? I guess the best option then is, if using a 12 volt system try keep lighting to 12 volt LED's and not use resistors. Fortunately, all my station lights, street lights, cars lights and burger bar are all 12 volt. The Railway Inn was the only 6 volt lights with resistors are those used to light the signs, they were purchased to suit the need; suitable lights with shades. Knowing what I know now I would have left off the resistors and connected two lights together to the one switch. Could I have wired to lights together back to the one switch and done the same with the other two lights but, taken both back to the same switch? ALWAYS use a resistor with LEDs. But note that '12 Volt' LEDs have the correct resistors built into them. They will work perfectly, as long as you don't use a power supply, that actually puts out more than 12 Volts - despite what the label might say. If the power supply, isn't a regulated one, then almost certainly the voltage will be too high. Link to post Share on other sites More sharing options...
model-trains Posted August 5, 2016 Author Share Posted August 5, 2016 The Railway Inn is now in place and the lights, wiring and switches all done. I still have lights to add inside the Inn 7 new images added to the Gallery diary today for anyone interested in the progress. They includingTrain-Tech signals, SC1 decoders and the feathers added to the Train-Tech signals Below is an additional view from the Station platform. Train-Tech signal with CR Signals route indicator added also installed. These are well proportioned, easy to install and I think they look good. I hope you like the progress so far. Link to post Share on other sites More sharing options...
model-trains Posted August 12, 2016 Author Share Posted August 12, 2016 I have included two lights in the base of the layout which will light up parts of the Railway Inn when switched on. They are 6 volt with resistors, wires in parallel. There are two cut outs in the Railway in base so that it slots over the lights with ease. The ground/first floor is removed from the left hand section and part of it above the Inn's reception to give a little light above, it doesn't show well in the image but does work well. The external lights over the signs are connected to a snap together plug/socket which slots nicely behind the Inn. Holes are also left in the back of the Inn for ventilation. Additional images have also been added to the Gallery for anyone wanting to view them. Link to post Share on other sites More sharing options...
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