Hello. I am working on lighting my new expansion. This means street lights and all of the structures. I have a mix of LED and grain of wheat bulbs. The LED draw 20 mA and the 12v bulbs draw 70mA. I know how to calculate capacity for my power supply (I am using a 15v power supply with a 5000 mA output), but i am wondering what happens if i mis-calculate and wire too many lights for the supply. Do they stop working? Does it burn out the power supply? Do the lights still work, but at a lower light output? I am hoping not to exceed my capacity, but I an also hoping not to learn a lesson the hard way. Has anyone had this happen to them? I would love to hear your experiences. Thank you.
I am assuming you use resistors on the GOW bulbs...? What kind/level of resistor do you use. I have to clean up the birds nest of wires soon and was thinking about doing the resistors to prolong the life of the bulbs....
I and most operate LED's at about 10 ma, not 20ma. Twenty ma is the max for LED's. LED's are current devices, not voltage devices. Bulbs are voltage devices. Some do use a resistor in locos with a bulb. What kills bulb life is the surge when being turned on which is why some run them at a lower voltage. If they use an old power pack, they lock down the control on the layout.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
This is great information. Thank you. So I can acquire a buck converter, tune down the voltage, and run as many GOW bulbs at the reduced voltage with more electrical efficiency and a prolonged life...? Do these buck converters have a read out display, or will I need a separate voltage and amperage meter to fine tune the levels?
Kerry
HOmainlineVery interesting. I had not heard of a buck converter until now. Aside from the OP's use of it as cited here, for what other applications might one need - or want - to use a buck converter on a DC layout? Mine is small (5' x 7'), so the need and capacity for LEDs, GOWs, etc. are limited.
RR_Mel HOmainline Very interesting. I had not heard of a buck converter until now. Aside from the OP's use of it as cited here, for what other applications might one need - or want - to use a buck converter on a DC layout? Mine is small (5' x 7'), so the need and capacity for LEDs, GOWs, etc. are limited. There are two types of Buck Converters. The one discussed above are down converters. They convert from a higher DC voltage (8-32 VDC) to an adjustable voltage and current regulated DC voltage (.8-the input voltage). The other Buck Converter is an up converter. It converts the input voltage (8-32VDC) to .8 to as high as 42 VDC also regulated. Both come in a variety of current ratings from below 1 amp to 30 amps. All of the converters that I’ve dinked around with have excellent regulation and are very well filtered and very stable. They provide a clean well regulated adjustable DC voltage that can power any thing on a layout. I highly recommend them, much better than using a regulator, very efficient and almost no heat dissipation. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
HOmainline Very interesting. I had not heard of a buck converter until now. Aside from the OP's use of it as cited here, for what other applications might one need - or want - to use a buck converter on a DC layout? Mine is small (5' x 7'), so the need and capacity for LEDs, GOWs, etc. are limited.
Mel,
I believe you misread the question.
HOmainline Mel, I believe you misread the question.
RR_Mel HOmainline Mel, I believe you misread the question. My primary use is to power Grain of Wheat bulbs, my LED signals and crossings. All of my HO vehicles have 1mm 1½ volt micro bulbs. My layout requires many voltages to operate the various accessories. 1½ volt bulbs, 4½ volt Miller signs, 5 volts for my Arduinos that drive many different things from lighting to automated goodies. 8½ volt GOWs for structure lighting and street lights. 9¼ volts for the GOWs driven with an Arduino, and 10 volts for miscellaneous motor driven automation. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
HOmainline
Mel, I believe you misread the question.
Now, that gets to the gist of my query: applications.
I didn't expect anyone to guess what my supplemental power needs may be (I still don't know them all), nor was I asking about the different types of converters, what they do or a description of such. Since I'd never heard of them before, I was simply curious as to their various uses and when (and why) they may be needed.
Let me emphasize the above about LEDs being current devices and bulbs being voltage devices.Don't try to run them off the same power supply. Just don't. Trust us, you'll be much happier.
Disclaimer: This post may contain humor, sarcasm, and/or flatulence.
Michael Mornard
Bringing the North Woods to South Dakota!
Not that I don't trust you, but what is your experience with running LED and bulbs...? Sounds like you may have had something happen and learned a lesson the hard way...? I am curious. I am the originator of this topic and I am interested in all advice and experience. Trying to wire my layout and I'm moving up from simple wiring to advanced with all kinds of lighting features, animations and sensors/indicating devices.
Thank you for clarifying. That is how I am going to re wire my layout. Separate power supply for LED and Bulb. I have dimmer switches for adjusting brightness of the LED and I will be installing the step down buck converters on my GOW bulbs. Thank you for all your insight and knowledge. I have learned much over the last few days. Cheers!
RR_Mel Kerry The Buck Converters are a pretty slick device for adjustable voltage needs. They are cheap, reliable and very efficient. My layout is in the garage and before I changed over to the Buck Converters I was using transistor regulators and I had to use a 4” fan to pull the heat out of my control panel from the lower current regulators. I mounted the higher current regulators on the outside of my control panel and they poured heat into the garage. The Buck Convertors don’t even get warm to the touch. I’ve had three operating for almost three years without any problems at all. As of today I have six converters mounted inside my now very “cool” control panel drawing a total of 13 amps from my 12 volt power supply with very little heat generated if any. Mel My Model Railroad http://melvineperry.blogspot.com/ Bakersfield, California I'm beginning to realize that aging is not for wimps.
Your layout must be as big as Grand Central Station. But without all those passengers!