Installing LED strips and other LED issues

[Bugsysiegals]

I'll be building kitchen cabinets in the next year and was interested in doing LED lighting as seen at IKEA.  I really appreciate you taking the time to share what you've done here, it will certainly help me, much appreciated, and great work!!

 

[Cheese]

The other alternative would be to use the reed switch to trigger a relay, and then have the relay handle the higher current to power the LEDS. Again, a few more components, but you wouldn't have the reeds singeing themselves together.

Ya, thanks for bringing that up. That's one of the paths I actually thought about. However, because there are 4 separate cabinets, I'd need at least 4 solid state relays plus voltage in to power the relays etc, etc. Things just started to get complicated quickly. The microswitches kind of kept the clutter to a minimum.  [smile]

 

[Cheese]

Here's a real nice compact solution if you're short on space. It's one of the latest Diode LED products. It combines a wall box mounted driver with an integral dimmer. They come in 3 different wattages and in 4 different colors. They aren't inexpensive though, the 60 W model runs $190.

I put in the 60 W model on the other side of the kitchen and run 11' of Ultra Blaze in CHROMAPATH® Slim aluminum channel for under counter task lighting along with 3' of Ultra Blaze imbeded in a walnut counter top.
https://www.diodeled.com/wp/wp-content/uploads/2019/04/2019-diode-led-catalog-041119B-web.pdf

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Here's another new product from Diode LED. It's flexible and goes around corners.

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[Michael Kellough]

Can you put one of those 40 watt Meanwell drivers in a wall box? If so, would you switch the power to the driver or the output to the led’s?

 

[RKA]

This is great, I'm starting to understand all the bits involved.  The hall effect sensor is intriguing, but my googling is turning up stuff that doesn't look like it's packaged for plug and play use.  Ideally I would want to buy a kit with the switch, relay, driver and LED's all together and ready to wire into the cabinet. 

So here is a question.  I don't know enough about the wiring yet to understand if this is right.  I'm designing a cabinet for my wife (she would say it's going nowhere, but she doesn't appreciate that thinking is half the work!  ) which will be waist high about 600mm/24" wide, with two symmetrical doors and a drawer (above or below the doors).  So I need:

• 2 20" sections of the LED tape
• 1 driver (how much output?)
• 2 hall effect switches
• 1 relay?
  

There will be two LED strips inside the cabinet, and if either door is opened, I want both LED strips to light.  I think that means both switches need to be connected to the driver and relay so either switch can turn the lights on.  Does that sound doable?

*Edit*
One more thing...I know I want a warm light (2700K tops), but I'm not sure about the intensity.  In case the two strips end up being too bright, I may need to dim them, but really only once to get it where I want.  Do the drivers come with an integrated dimmer where I could make the adjustment before hiding the driver away in a recessed compartment hidden in the cabinet?

 

[Cheese]

Can you put one of those 40 watt Meanwell drivers in a wall box? If so, would you switch the power to the driver or the output to the led’s?

I don't think a 40 W driver will fit in a wall box Michael. However you may be able to put 2 each 20 W drivers in a wall box and run them in parallel. That's exactly what I'm doing with the photo of the 2 Triads because of space limitations.
https://led.meanwell.com/productSeries.aspx#tag-6-57

Here you can see the 40 W Triads stacked on top each other because these are inside a small metal box I placed in a rear concrete step that I poured.
An 80 W driver would never fit in this small space.

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And here's an example of the size of a 60 W driver.

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If it's for task lighting, definitely switch the 120 AC that goes to the driver.

Also choose a driver that will provide you with more power than you need. 15% to 20% is the rule of thumb. So if you know the LEDs will draw 20 watts, choose a 25 watt driver.

I use CV constant voltage drivers which serves probably 90% of the LEDs. Mean Well also sells CC constant current for those LEDs that require them.

 

[Bernmc]

[member=21249]RKA[/member] If you have limited electronic smarts, then a simple relay setup would be the way to go (the Hall effect switch is kind of ‘fun with over engineering’). The idea is simply to separate the high current LED circuit from the low current switch - Reed switches have tiny little filaments of moving metal, so any significant amount of juice running through them can weld them together.

Below is a very simple doodled concept using a solid state relay (a relay that is all electronics inside, rather than the mechanical device that works with a coil and magnetism). Solid state relays draw much less current than the mechanical relays, so it opens up options for low power solutions. Just be aware that some solid state relays are designed to handle an AC output, and some for DC - the LEDS will want DC.

You’ll be able to find equivalents in yankland or fleabay if you dont want to buy direct from the sweatshop, but something like this from Aliexpress would work. It only needs 12 milliamps on the input, so I suspect you’d get decent life out of a 9V battery, but you’d need to experiment.
Mount it to another bit of looomininininum if you’re running lots of strips (spec says anything over 10amps needs a heat sink - I doubt a couple of short runs of drawer lights will need that much)

If you want everything mains powered, there are plenty of power supplies/drivers that have multiple outputs, so you can run one output on the reed switch/drawer sensor side, and another on the LED strip side.

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[Cheese]

This is great, I'm starting to understand all the bits involved.  The hall effect sensor is intriguing, but my googling is turning up stuff that doesn't look like it's packaged for plug and play use.  Ideally I would want to buy a kit with the switch, relay, driver and LED's all together and ready to wire into the cabinet. 

So here is a question.  I don't know enough about the wiring yet to understand if this is right.  I'm designing a cabinet for my wife (she would say it's going nowhere, but she doesn't appreciate that thinking is half the work!  ) which will be waist high about 600mm/24" wide, with two symmetrical doors and a drawer (above or below the doors).  So I need:

• 2 20" sections of the LED tape
• 1 driver (how much output?)
• 2 hall effect switches
• 1 relay?
  

There will be two LED strips inside the cabinet, and if either door is opened, I want both LED strips to light.  I think that means both switches need to be connected to the driver and relay so either switch can turn the lights on.  Does that sound doable?

*Edit*
One more thing...I know I want a warm light (2700K tops), but I'm not sure about the intensity.  In case the two strips end up being too bright, I may need to dim them, but really only once to get it where I want.  Do the drivers come with an integrated dimmer where I could make the adjustment before hiding the driver away in a recessed compartment hidden in the cabinet?

Raj if you want a plug & play package check out Haefle. They offered something along those lines for wardrobes a few years back.

I'd stick with microswitches because of their simplicity and reliability. I also looked at hall effect but that approach wasn't too friendly.  [smile]

Here's a visual aid I slapped together. 2 LED strips connected together at the top. The driver is plugged into 120 VAC. One leg of the 12 volt output connects to the LED, while the other leg of the 12 volt output connects to each microswitch. Each microswitch connects to one of the LEDs. If either switch is triggered, both LED tapes will light.

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Let me get back to you on the dimmer. I have one that's maybe the size of a 1/2" cube. It's really tiny. I use it for adjusting light levels. I'll go down and dig in my LED SYSTAINER... [eek]...that's a fact. A Systainer actually stuffed with LED items. How NERDY is that?  [crying]

 

[Cheese]

Hey [member=69245]Bernmc[/member] would you be able to run multiple reed switches to the relay?

Is there a practical limit on the number?

 

[RKA]

[member=44099]Cheese[/member] Thanks for the pictorial, that makes it very clear (I would have been lost if you typed a paragraph).  So if I wanted to eliminate the battery and only have it powered from AC, does the relay need to be spec'd for that (because it would see 120VAC)?  Same for the reed switch?  And any guesses if any wood can be present between the magnet and switch?  The idea would be to conceal all the switch elements so it's not obvious how the light is activated, other than the movement of the door (that's why I didn't look at the microswitches, I think it would be impossible to conceal them).

 

[Bernmc]

Hey [member=69245]Bernmc[/member] would you be able to run multiple reed switches to the relay?

Is there a practical limit on the number?

Yes, you could just parallel them, as long as you want the situation where any switch powers the same LEDs (eg any drawer switches on all the lights, as in Raj’s requirement). They’re only activating the relay, so you could have as many as you want - it’s the other side of the relay doing the heavy lifting.

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[Cheese]

1. So if I wanted to eliminate the battery and only have it powered from AC, does the relay need to be spec'd for that (because it would see 120VAC)? 
2. Same for the reed switch? 
3. And any guesses if any wood can be present between the magnet and switch? 
4. The idea would be to conceal all the switch elements so it's not obvious how the light is activated, other than the movement of the door (that's why I didn't look at the microswitches, I think it would be impossible to conceal them).

4. So Raj, let's start with the easiest answer first, if i'm understanding you correctly, you want this project to perform virtual MAGIC for your wife to justify why you spend so much time on the FOG.  [poke]  Ya ...I get that.  [smile]

1. I have limited experience with solid state relays but I believe you need to match the incoming voltage. They are pretty cool and certainly blow away the traditional variety. They're so small and so quiet. [member=69245]Bernmc[/member] may want to chime in here.  [smile]

2. Reed switches are usually rated by current capacity, but because in your application the reed switch is only being used as a signal carrying switch and not as a current carrying switch, current capacity really doesn't matter.

3. There can be some wood between the magnet and the reed switch. It all depends upon the strength of the magnet and the distance of it from the reed switch. Trial & error are the words to live by here. Just play around with it and you'll get the feel. Also understand that the lineal position of the magnet relative to the reed switch can make a difference because the position of it determines the size and the force of the magnetic field. That's the reason I fabbed up that "mini drawer" to experiment with the positional issues between the magnet and the reed switch.

We'll be interested in your results.

This is the unit I use for adjusting brightness. It's really tiny.

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https://www.luxeonstar.com/500ma-externally-dimmable-buckpuck-dc-driver-leads

 

[RKA]

Thank you [member=44099]Cheese[/member] and [member=69245]Bernmc[/member] , I fear Ive stepped into another rabbit hole.  Just another day at the office I guess.  [smile] And Cheese, “magic” is dead on!  Since nothing is built yet, I have complete control (1% influence) over the design parameters of this little project.  Once I identify the bits I need, I can modify (ask for permission) the cabinet to accommodate the magic beans. 

And sorry, I think these unique requirements went outside the scope of your multi part series.  I can create another thread if you want to keep this one simple?

 

[Cheese]

Raj if you're looking for plug & play, you may want to consider some various Diode LED products. An assembled product would include everything you need except for the driver and switching mechanism. They have a new product called Spotmod Slik LED Panels.


They also offer fully assembled light bars.https://www.diodeled.com/cascade-led-light-bar.htmlhttps://www.diodeled.com/tru-link.html

Puck lights.https://www.diodeled.com/triant-led-puck-light.html

Or just generally assembled product.https://www.diodeled.com/products/fixtures.html

Sensors & dimmers.https://www.diodeled.com/products/led-control.html

 

[Cheese]

I've had led strips explode and catch fire in the past which worried me, they were covered in a kind of clear plastic sheath which i guess insulated them.

So [member=70385]Russty[/member] , this response goes back to your previous experiences. I assume the LEDs you're talking about were waterproof LEDs. If so they probably had a profile that looked similar to this.

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Well the supplier of these LEDs suggested I just remove the liner of the VHB double stick tape and adhere this to any substrate I wanted to. So I did. I routed out some channels in stretchers that were part of a cabinet assembly and adhered the LEDs to the wooden stretchers after sealing the channels with 2 coats of sanding sealer.

I then decided to "burn in" the LEDs for a couple of days just to make sure everything was copacetic. So after 2 days of continual activation they looked like this.

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Day 3 looked like this.

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Day 4 looked like this.

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And day 5 is when I decided to intercede.

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Upon closer inspection you can see burn marks on the LED covering. Even more surprising is that some are burned, some are really burned and some are not burned at all. That's the way it's always been with semiconductors, "catch as catch can."  They're all individual entities and they all age differently and in this particular incident, produce different levels of light and different levels of heat.

You'll also notice that they've been adhered to a wooden substrate. That's a big part of the problem. Wood is an insulator and it absorbs a minimum amount of heat and radiates none. The silicone waterproof barrier over the LED puts the final death knell on this product.

This LED can't rid its heat from the top and it can't rid its heat from the bottom. It just sits there and cooks. Possibly, if it's in a water bath it may survive, however that's not how these are commonly used. They're typically used outside when moisture is a problem.

I do think however, if these were placed on an aluminum heatsink, these issues would be mitigated to some degree. Keep them cool is a mantra.

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[Cheese]

Here's a good article on drivers & power supplies. They also talk about Constant Voltage CV versus Constant Current CC. The subject of dimmers is also talked about.
https://www.ledsupply.com/blog/understanding-led-drivers/

 

[Cheese]

Can you put one of those 40 watt Meanwell drivers in a wall box? If so, would you switch the power to the driver or the output to the led’s?

Hey [member=297]Michael Kellough[/member] I just received a 20 watt Meanwell for an edge lit bathroom shelf project. Here's how it compares to the 60 watt and a single electrical box.

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[Michael Kellough]

Thanks! Excellent provision of information, as usual.

 

[Russty]

that is definitely consistent with what happened to mine, they were clipped across joists so were technically in free air so lasted a bit longer, i cant remember how long exactly but i reckon about 4 or 5 months before they started to dim and then a few more months before they started to pop and catch fire.

 

[Gregor]

... 4 or 5 months before they started to dim and then a few more months before they started to pop and catch fire.

They what?