Digging into what LEDs are in the strips

LED lighting strips come with specific LEDs in them, usually all the same LED part number. You can look up the stats on those LEDs and then do the math (so many LEDs in the strip and the strip is so many feet long) to come up with how the strip will perform:

• How many lumens (how bright)
• How many watts consumed

On the web at this site, you will find the specific specs for the LEDs commonly used in LED strip lighting:  http://www.saving-star.com/smd-led-comparison

Here's the table from this site:

 

In my next post, I will take an example and show how I compute what an LED lighting strip will do.

Let's look at an LED strip

Okay, let's use the LED info from the last post to evaluate an LED strip for sale on Amazon.

Here's one:

HitLights LED Light Strip - Warm White 3000K SMD 3528 - 300 LEDs, 16.4 Ft Roll
$8.49 Free Shipping for Prime Members
Link:  http://a.co/3CTtIos

This uses 3528's, which from the chart in the previous post has these specs per LED: 8.5 lumens and 0.06 watts. There are 300 LEDs in this strip, so doing the math we get:

• 9 lumens x 300 = 2700 lumens - divide by 16.4 ft gives 165 lumens per foot
• 0.06 watts x 300 = 18 watts - divide by 16.4 ft gives 1.1 watts per foot

What does 165 lumens per foot really mean? Well, let's look at the lumens for incandescent bulbs, which we're familiar with:

So 165 lumens per foot means something just over a 15 watt bulb - quite dim, actually. My module sections will be 6 feet long, so that's only 90 watts of light on the entire module, which won't be very bright at all. This LED strip is NOT a good choice for model railroad lighting, it's not bright enough.

Let's look at a high density/high brightness strip

Some LED strips are listed as high density strips using either double the number of LEDs and/or using LEDs that are extra bright. Let's look at one of these ...

LEDMO 2835 600LEDs Warm White LED Strip, 16.4Ft DC12V Non-waterproof 15LM/LEDs 3000K, 3 times brightness than SMD3528 LED, LED Ribbon, LED Light Strip, LED Strip Light
$10.90 Free Shipping for Prime Members
Link: http://a.co/1IRMXsJ

This uses 2835's. The chart in the previous post has specs for three different sub-models on this LED part number, so which one do we pick? The key is in the listing for this strip: three times brighter than 3528, which would be 9 x 3, or about 27 lumens. Ahah! That's the 2835a's So we'll take those specs per LED: 26 lumens and 0.2 watts. The strip lists 600 LEDs, so doing the math ...

• 29 lumens x 600 = 17,400 lumens - divide by 16.4 ft gives 1060 lumens per foot
• 0.2 watts x 600 = 120 watts - divide by 16.4 ft gives 7.4 watts per foot

We know from the lumens chart in the last post that 1060 lumens per foot is ~70 watts of incandescent light equivalent per foot. My module sections will be 6 feet long, so that's 420+ watts of light spread over the entire 6 foot length, which is plenty bright. This strip will work good to light a model railroad module.

So that's how to evaluate LED lighting strips and to pick something that will work!

Update: Corrected this post ... this strip actually has 600 LEDs, not 300. Some of the specs say 300, but most of the specs say 600 LEDs, so we're going with the 600 as correct because lower in this listing where Amazon gives the detailed specs for this strip it says:

Specifications 
* LED Type: High Quality SMD2835 LED Light StripTop LED, 3 times brightness than SMD3528 LEDs 
* Quantity of LED: 600 LEDs 
* Input Voltage: DC12V 
* Light Color: Warm White (2800-3000K) 
* Light Output (lumen): 15LM/LED 
* Length: 16.4Ft (5m) 

UPDATE 2022-04: The above LED strip is no longer available. The closest equivalent appears to be this one that's now $23 for 10 meters -- the no-longer-available one above was 5 meters for $11, so roughly the same price. Since you can cut these strips to any length, then same difference ...
https://amzn.to/3MzaGBg

I would argue that it makes

I would argue that it makes more sense to present this data in terms of florescent tube equivalency since an Incandescent bulb is a point source and an LED ribbon and a tube are line sources. The lumens are distributed differently

It's also worth noting that unlike both other light sources LEDs, at least 5050s and I assume 2835s are similar only have about 120 degrees of spread. a Tube or standard bulb has 360 degrees of spread (in fact, standard bulbs have more since they don't devolve to line sources),  so it wastes a large portion of the light in directions that you don't care about and a reflector can only recapture so much. So 40 watt equivalent of LED that is all directed at the layout is significantly more lumens than a 40watt Tungsten bulb. Tubes being somewhere in the middle.

If you don't mind me saying Joe, one of the things that always struck me about your SL1 lighting was how much lumens you wasted lighting up lumber you never wanted to see. Though you probably saved money on your heating bill.

Low wattage incandescents

The low wattage incandescents actually were not that bad. I had 2800 watts of low watt incandescent light in the room, or the equivalent of 28 bulbs of 100 watts each in the room. The room temperature would go up a about 5 degrees in 3-4 hours just running the lights in an otherwise empty room.

Compare that to Rod Loder's old railroad which used 60 watt bulbs throughout and had over 10,000 watts in the room. Rod needed a room air conditioner because the room temp would go up 10 degrees in about 30 mins.

Thankfully those days are all now behind us!

I found that light color is

I found that light color is an important consideration when selecting LEDs.  I noticed that you selected warm white.  You'll find that the light is much different with other light colors.  I was told when selecting LEDs for the house that light color had a lot to do with the quality and usability of light.

Last Fall I bought a 6 pack of 60 watt equivalent LED bulbs in daylight color on Amazon.  I put two in a ceiling fixture in the family room and found the light to be very bright and harsh.  I took them out and put in bulbs that were of the same rating but in warm white.  Much better for the family room.  I put the daylight color bulbs in my wife's sewing room and she loves that light for sewing.

I changed out the fluorescent bulb over my modeling workbench for a $10 bathroom vanity mirror fixture I bought and Lowes and put three of the 60 watt daylight bulbs in it.  It's much better light for that kind of work.  I certainly wouldn't see nearly as well with warm white bulbs in it.

When the layout building is finished and modules move from the basement I plan on using daylight colored LEDs over the layout.

Jeff White

Alma, IL

Actually, the Color

Actually, the Color temperature isn't quite as important as the Color Rendition Index or CRI.

In the bad old days, your standard tube florescent had a CRI of around 65 (on a scale of 1-100) which is pretty bad. That's why in photographs things often looked exceedingly green.

In simple terms, CRI tells you how capable a source of light is going to be at rendering minute differences in color. So if you have a beige called mushroom and a beige called sand. They may look exactly the same under a light with a CRI of 65, but the difference will be plain as day under lights with CRI of 80+

CRI is independent of color temp and even the cheapest of the SMD LEDs we're discussing here have a CRI of 80+ which is good. If you're picky, you can pay for CRI of 90+ in LED or florescent. 

And even your standard big box retailer T8 and T12 tubes and generic CFLs are going to have reasonably high CRI now. So some of those old rules of thumb no longer apply.

Now, it is correct that "Daylight" bulbs, meaning something with a color temp up in the 5K-6.5K will look more like what you'd see under natural light. Defined in this case as the color of light from a northern exposure window on a sunny day. But your entire layout doesn't have a northern exposure.

I myself prefer to use theater lighting by which I mean RGB+W. My thought is to use "Daylight" and use the RGB to set the level of warmness. This will let me simulate everything from night to high noon at the equator. Plus, you can dim LEDs.

LED Ribbons turn theater lighting from an expensive chore, to easy AND there's an easy upgrade path to automated control 

This is the first video I found showing it.

And we already know all about Arduino and how awesome it can be on MRH.

Here's a good webpage that's in reference to home decor, but I find it a good start on what all of this means

http://www.thekeystocolor.com/why-color-often-goes-awry/

I am really excited about

I am really excited about LEDs, from an energy source and environmental standpoint, and am gradually replacing existing bulbs (mostly the small florescent). I did have an issue with one pendant fixture where I installed  a 50 w equivalent LED in place of a small florescent of about the same equivalent wattage. After about 4 or 5 hours the socket with LED in it failed. It appears to have gotten quite hot from the looks of it. The LED still works in other sockets and doesn't appear to generate much heat.

I mentioned this to a friend and was told that if the socket wasn't wired correctly, i.e., neutral and hot wires reversed, and this would be the cause of the problem. I kind of find this difficult to believe considering things like table lamps can be plugged in either way, albeit sometimes not smoothly.

Has any one else had this type of experience?

S

Heat from lighting

Joe --

First, thanks for all the research you do (paint, trackwork, LEDs, etc.) and publish,  Wonderful resources.  I'm looking forward to reading about your choice for LED layout lighting.

Second, heat from lighting can be secondary to heat from people.  My 140 sq. ft. layout room gets a lot warmer when there are 5 of us present during an op session than it does when I'm up there working alone.  The present lighting is 10 fluorescent bulbs of 4 ft. length.

A portable air conditioner, added to try to cope with the warm summers, struggles to keep the temperature reasonable during op sessions.  Since the SMR is a switching layout, maybe there's excess heat being generated from all the thinking the operators have to do?

People heat

I seem to remember that someone, probably Robert Heinlein in "Have Spacesuit, Will Travel," stated that the human body shed about as much heat as a 100W bulb. 

So yeah, operator body heat is something to consider when heating/cooling a layout room. 

@STEVEN

A hot socket can be caused by one or more problems. If the socket is designed with the hollow rivet for connecting the thread body and the rivet becomes loose, then this can cause heating from a poor connection (especially if the rivet metal is disimilar to the threaded body. A badly tarnished or corroded center contact can also cause heat as the corrosion causes a resistance and the current flowing through that resistance generates heat. Also, the connection of the wires may be poor and/or the contacts in the switch (assuming the socket includes a switch) can also generate heat. Another source of heat is the wire itself - certain models of devices in the mid-century (around the '50s) used aluminum wire, which has been discontinued, since it makes poor contact and also has less conductivity than copper.

Considering the cost of a replacement wire and socket, it may be wise to discard the cord and socket and replace with quality materials. A socket that heats in this manner can be a fire hazard.

Your body will add...

300 btu's of heat per hour.     John

Bill D., Thanks for replying

Bill D.,

Thanks for replying and for the info. The socket and wire were replaced after the 'incident'. Haven't reinstalled the LED bulb again...yet. I want to be around when I do so I can be aware of any issues in the making.

Thank you again,

S

Warm White Vs Bright White & Color Rendering

I have been using LED strip lights for several years now and one thing I found is that LED lights often have a narrow color temperature range, especially the bright white lights, so they don't render the full spectrum of colors in the scenery. The scenery appears somewhat monochrome, making it more difficult to see detail, and it even seems to affect depth perception.

My solution for this was to use two LED strips, one warm white, and one bright white.  This solves several problems;

1) I'm using SMD3528 LED strips, high density (120/meter).  At 3 feet above the layout, one LED strip did not provide adequate lighting.  Adding a second strip gave me the brightness that I needed.

2) Having two strips of different temperature range provides a broader color spectrum.

3) I power each strip from a separate power supply, so I can adjust the brightness of each color independently.  This allows me to fine tune the lighting to my liking.

In the photo below, the camera was facing directly into the lights, which made the rest of the room look dark.

This photo better represents the lighting level on the layout.  As you can see it's well lit.

Greg Hartman

Reading Railroad in N Scale

Clever idea!

That's a very clever idea! 

Since these strips use far fewer watts than my old incandescent lighting, having more than one strip should not be a problem. I'll have to consider the two-strip idea.

The other option might be to do full RGB strips and then I could get all kinds of colors, including moonlight and sunrise/sunset.

Huge variety

There is a huge variety of these led strip lights available, it really makes it hard to choose. You can get strips that have one row of cool white and a second row of warm white, there are also the ones mentioned that have RGB and white LED's, I believe you can control each separately. My understanding is that as of late 2016, there are new higher effiency led strip lights, I thought they were in the 3528 size, but I might be wrong. The problem with most of these is that they don't usually give you enough specs to tell for sure what you are getting!

I bought some strips that, instead of being on the tape are made on thin aluminum. I thought this would be a good idea as the metal acts as a heat sink. I suspect now that they aren't as efficient as the newest ones, but they have turned out to be plenty bright enough. These were 5000 K colour temperature, at first I wasn't sure about the colour, but I think it was a matter of getting used to them. I have also installed an RGB strip towards the backdrop to do evening/morning effects.

My understanding is that you should compare the lumens per watt to choose the most efficient, but many vendors don't give you this information, especially the ones from China.

One other consideration, try to buy all that you need at once, if you re-order, the lights may not be the same, these LED's are evolving rapidly, so in 6 months they may be changed completely and might have a different look to them.

There are more knowledgeable people out there than me on these things!

Ebay Vs Amazon.

What would the advantages using amazon vs Ebay as a source for the LED Strips.  For instance, the vendor for Amazon sells a 5M strip for arond $12, while on Ebay I have a few different vendors who sell similar color (need to check the CRI specs) for 1/3 the price. Are the ones from Amazon of higher quality?  The saying "buyer beware" and "you get what you pay for" comes to mind, on the other hand, paying more for something does not mean you are actually paying for better quality. Thoughts?

Ken L.

PS Thanks Joe for starting this thread as I believe LED technology has rapidly advanced to a point where it is very affordable for even a large model railroad to invest in them!  KDL

If you have Prime, then free

If you have Prime, then free shipping. Also Amazon stands behind the sale.

Prices

A lot of the cheap ebay stuff comes from China.  It is a bit of buyer beware.  I recently purchased some LEDs (not strips, but this vendor does sell strips for cheap) and other small components from a China vendor because they were considerably cheaper and appeared to be the same thing.  Others here had reported using this vendor and recommended them.  I can't tell the quality because I've never received the items and it has been almost 3 months.  I sent them a message and they have not responded.  Next Thursday ebay will step in to do their work.

I'm not saying the vendor is crooked, but what I am guessing is that they are OK if 1-2% of their packages never make it and they get negative feedback.  From the feedback, if you don't receive your package, they simply ignore you and let ebay refund your purchase, unless you are 30 days past the estimated delivery date, then you're screwed.  Really, it comes down to if you're comfortable being that 1-2% and ensuring you put in your claim with ebay if it goes past the delivery date.  

Buyer beware.

Amazon vs eBay

A lot of product coming from China may be exactly the same item but not tested to UL standards and without the label. The ratings and comments have been helpful for me to make decisions about buying electrical components such as batteries. UL told me that if it doesn't have a label then they won't test them and may be headed to another market.

Body Heat.

As Bob Hayden once said, he runs his trains much like I And most modelers do 95% of the time. Alone. 3-4 of us get together once a month and and I can tell you the only time it gets heated is when someone says Guilford is a nice scheme!! I like the idea of one cool white and one warm white strip together. But has anyone replaced their lighting with LEDs? I have  a cool white and a warn white bulb in my florescent fixtures. Im thinking of ordering the rolls that Joe linked to. My question is , is it bright enough? Has anyone photos they can post to show how bright it is? ( I know thats two questions!)

Thanks Ted 

2 strips

I did the t strip approach also. It works very well.

Although on my next layout I am considering ditching the strip lights in favor of simplified overall room lighting like Mike Confalone does. 

Simplicity is a wonderful thing.

Room lighting and the shadowbox

Yep, although room lighting won't work for shadowbox modules like I'm planning to do. So LED strips it is.

By the way, if you do the math, LED strip lighting is becoming one of the cheapest lighting methods out there.

On my Siskiyou Line 1, I first used low wattage incandescents every two feet, at a cost of about $3 a foot, with a bulb replacement cost of about $50 per year. Across 26 years, that's an additional $1300. Divided by my 250 feet of running distance for all my lights that's an additional $5 per foot, for a total cost per foot of $8.

The LED strip lights with power supply are about $2 per foot ($4 per foot if you use two strips) and you're done. They should last the life of the layout. 

LED Rope Lights

Prior to laying the track on the lower level, I have strung to LED rope lights (Menard's, 48' in length, $36, warm white only) under the upper deck as a test.  They will supplement the florescent light fixtures in the room.   Hope this helps anyone who may be considering this method. Pretty cheap and easy as the plastic clips hold the rope well.  

Warm regards, Bagley