k0ua
Epic Contributor
So the wife has complained for some time that there was not enough light above her sewing machines. There are two 4 foot florouscent tubes up in the suspended ceiling above the machines behind some plastic diffusers. I measured the lux with the lightmeter app on the smartphone and it said 461 lux right on top of the sewing machine which is really about 4 foot from the diffusers. So I thought about this a bit, and here is what I built. Oh, yes I know there are LED 4 foot direct replacement tubes, but I wanted to try this method and see how it would work out.
Materiels: 4 foot 1x4 pine board, 4 new work electrical boxes (modified, because they were so cheap at 0.98 cents each), 4 of the plastic lamp holders, also cheap at $1.38. and 4 of the Cree LED 9 watt 65 watt equivalent BR 30 lamps, 6 foot 16 gauge extension cord
I know the Cree brand is RFI free, that is one reason I stick with them
I cut and laid out the pine 1x4 and mounted the boxes after I cut their ears off in the bandsaw. I cut 14 gauge wire to the proper length and cut the end off of a new extension cord.
BE SURE to observer polarity of the cord. The ridged side of the cord is the neutral , also the fat prong on the plug, and it goes to the white screw on the lamp socket base. You must observe polarity because you don't want the lamp socket outer ring to be hot. The center pin connection of the lamp base should be hot. The hot should be what is switched by your wall switch also, NOT the neutral. This can cause LED's to glow after being switched off, not to mention a safety hazard if someone attempts to work on the wiring and just trusts the wall switch.. Remember safety first. If you don't understand these concepts then don't try to build something like this.
After assembly of everything, I did some "sanity checks with an ohm meter before applying power to make sure all polarity was observed in each connection, and then plugged in some old incandescent lamps which measure 25 ohms cold each and with 4 of them I measured about 6 ohms of load. Time to plug in and fire it up. All went well.
I mounted the completed unit up in the ceiling above the diffusers panels and screwed in the new LED floodlights.
I went from 461 lux to 1655 lux. A big noticable improvement while reducing my watts consumed from 80 to 36. Not a bad deal, less than half the power and over 3 times the light.
Notice a few things in the photos. One is a photo of the fluorescents in operation showing the interference lines in the photo. This is how you can supposedly tell if the ballast is a magnetic or electronic ballast. The magnetic is supposed to have severe lines in the photo like this one when photographed with a smart phone.
Notice my multiple sanity checks with the voltmeter before any power is applied. I don't like electrical surprises much. Notice how I am bending the wire ends clockwise so that when the screws are tightened on the fixtures, they tend to keep the wire under the screw heads instead of camming it out if you bent them the other way.
View attachment IMG_20160112_131207029.jpgView attachment IMG_20160112_131254270.jpgView attachment IMG_20160112_131120845.jpgView attachment IMG_20160112_124927845.jpgView attachment IMG_20160112_125022712.jpg
Materiels: 4 foot 1x4 pine board, 4 new work electrical boxes (modified, because they were so cheap at 0.98 cents each), 4 of the plastic lamp holders, also cheap at $1.38. and 4 of the Cree LED 9 watt 65 watt equivalent BR 30 lamps, 6 foot 16 gauge extension cord
I know the Cree brand is RFI free, that is one reason I stick with them
I cut and laid out the pine 1x4 and mounted the boxes after I cut their ears off in the bandsaw. I cut 14 gauge wire to the proper length and cut the end off of a new extension cord.
BE SURE to observer polarity of the cord. The ridged side of the cord is the neutral , also the fat prong on the plug, and it goes to the white screw on the lamp socket base. You must observe polarity because you don't want the lamp socket outer ring to be hot. The center pin connection of the lamp base should be hot. The hot should be what is switched by your wall switch also, NOT the neutral. This can cause LED's to glow after being switched off, not to mention a safety hazard if someone attempts to work on the wiring and just trusts the wall switch.. Remember safety first. If you don't understand these concepts then don't try to build something like this.
After assembly of everything, I did some "sanity checks with an ohm meter before applying power to make sure all polarity was observed in each connection, and then plugged in some old incandescent lamps which measure 25 ohms cold each and with 4 of them I measured about 6 ohms of load. Time to plug in and fire it up. All went well.
I mounted the completed unit up in the ceiling above the diffusers panels and screwed in the new LED floodlights.
I went from 461 lux to 1655 lux. A big noticable improvement while reducing my watts consumed from 80 to 36. Not a bad deal, less than half the power and over 3 times the light.
Notice a few things in the photos. One is a photo of the fluorescents in operation showing the interference lines in the photo. This is how you can supposedly tell if the ballast is a magnetic or electronic ballast. The magnetic is supposed to have severe lines in the photo like this one when photographed with a smart phone.
Notice my multiple sanity checks with the voltmeter before any power is applied. I don't like electrical surprises much. Notice how I am bending the wire ends clockwise so that when the screws are tightened on the fixtures, they tend to keep the wire under the screw heads instead of camming it out if you bent them the other way.
View attachment IMG_20160112_131207029.jpgView attachment IMG_20160112_131254270.jpgView attachment IMG_20160112_131120845.jpgView attachment IMG_20160112_124927845.jpgView attachment IMG_20160112_125022712.jpg
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