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glatt · 01-14-2015, 10:50 AM

I was inspired to order some cheap LED rolls and a transformer from China through ebay. I got these LEDs, and this power supply.

What does it mean that this power supply is a "switching" power supply? I ordered the stuff on Jan 3, and it arrived from China on Jan 13th. Very impressive for free shipping.

At first I was confused when trying to figure out what the brown, blue, and yellow/green wires were for. But with a little Google, I found out brown is hot, blue is neutral, and yellow/green is ground. Then I dug through my junk piles and found an old iMac power cord, and cut it open to wire to the power supply. It also used brown, blue, and yellow/green, so it was easier than I expected to wire it up. I had ordered a 45 watt power supply, and wanted to see if it would drive both rolls of LEDs wired in parallel. It did!

So here are some pictures. This shows both rolls lit up:
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Name: 15657160664_e0e41b23c2_z.jpg
Views: 183
Size: 77.0 KB

And for this one, I unwound one of the rolls a little and aimed at the counter so I can get a sense of the color and brightness. I like it. Not blue at all. A little whiter than the halogen hockey pucks under the cabinets now, but not obnoxiously so. And the brightness is good. This was taken with the ceiling lights turned off.
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Name: 16277797391_960e2dee49_z.jpg
Views: 200
Size: 72.4 KB

I'm going to use the existing halogen hockey puck wiring. They were wired years ago by an electrician who put switched outlets under the sink, and plugged the halogen power supplies into those outlets. I can just plug my new power supply into those same outlets and use the existing wiring to the halogens.

One thing I noticed is that after a couple minutes of being plugged in, the rolls of LEDs started to get a bit warm. I guess it's the cheap quality with the black resistors after every third LED on the strip. They were only $9 after all. I unplugged the power supply when I noticed the heat. I didn't want to melt the double sticky tape on the back of the strips. I am hoping that once the LEDs are installed, the heat won't be too bad because the strips will be unrolled and the heat not so concentrated. One of the reasons I wanted the LEDs instead of the halogens is that the halogens get hot and can melt forgotten chocolate chips on the bottom shelf of the corner pantry cabinet.

So this weekend, I'll have some time to install these permanently. I'll make sure to update the thread with better pictures that show before and after shots with identical white balance and exposure settings.

01-14-2015, 10:50 AM	#585
glatt ™ Join Date: Jul 2003 Location: Arlington, VA Posts: 27,717	I was inspired to order some cheap LED rolls and a transformer from China through ebay. I got these LEDs, and this power supply. What does it mean that this power supply is a "switching" power supply? I ordered the stuff on Jan 3, and it arrived from China on Jan 13th. Very impressive for free shipping. At first I was confused when trying to figure out what the brown, blue, and yellow/green wires were for. But with a little Google, I found out brown is hot, blue is neutral, and yellow/green is ground. Then I dug through my junk piles and found an old iMac power cord, and cut it open to wire to the power supply. It also used brown, blue, and yellow/green, so it was easier than I expected to wire it up. I had ordered a 45 watt power supply, and wanted to see if it would drive both rolls of LEDs wired in parallel. It did! So here are some pictures. This shows both rolls lit up: And for this one, I unwound one of the rolls a little and aimed at the counter so I can get a sense of the color and brightness. I like it. Not blue at all. A little whiter than the halogen hockey pucks under the cabinets now, but not obnoxiously so. And the brightness is good. This was taken with the ceiling lights turned off. I'm going to use the existing halogen hockey puck wiring. They were wired years ago by an electrician who put switched outlets under the sink, and plugged the halogen power supplies into those outlets. I can just plug my new power supply into those same outlets and use the existing wiring to the halogens. One thing I noticed is that after a couple minutes of being plugged in, the rolls of LEDs started to get a bit warm. I guess it's the cheap quality with the black resistors after every third LED on the strip. They were only $9 after all. I unplugged the power supply when I noticed the heat. I didn't want to melt the double sticky tape on the back of the strips. I am hoping that once the LEDs are installed, the heat won't be too bad because the strips will be unrolled and the heat not so concentrated. One of the reasons I wanted the LEDs instead of the halogens is that the halogens get hot and can melt forgotten chocolate chips on the bottom shelf of the corner pantry cabinet. So this weekend, I'll have some time to install these permanently. I'll make sure to update the thread with better pictures that show before and after shots with identical white balance and exposure settings.