Why You Should NEVER Use Non-Dimmable CFLs with Dimmer Switches. Find out what's working, what's not, and what to do about it. Leave this field blankAbout a year and a half after its first consumer-focused bulb went on sale, LED manufacturer Cree has released a next-generation design. This comes after the company has built up considerable expertise in the consumer lighting space, having released a number of different takes on the original 40W- and 60W-equivalent designs, including a BR30, a 75W, a 100W, the high color accuracy TW, and a 3-way bulb. Today Cree revealed the new “4Flow” design for its top-selling 40W- and 60W-equivalents, which will start at just $7.97. The bulbs received a considerable overhaul, with the glass exterior and Filament Tower being dropped entirely. The new design uses fewer LEDs (just eight) affixed to just two PCBs. Both PCBs are slotted and one snaps into the other using a spring connector, so no solder is required to insert the upper unit.

The 4Flow design is simple, lightweight, and uses very few parts. All of this signals that Cree was able to save considerably on material costs, which is in line with the $7.97 starting price of the 4oW model.Cats Meow Village Retailers As is immediately clear, 4Flow is a major departure from the original Cree LED. Fj40 Front Doors For SaleThat model used a complex Filament Tower, which had to be precisely bent into shape as well as a glass cover which was problematic from day one. Australian Shepherd Puppies For Sale San DiegoThe coated glass was not prone to breaking, but it was surely expensive to produce and it was heavy. The advantage was that the glass made the Cree look more like an incandescent bulb but — on the downside — the glue that held the glass cover to the base was a weak point.

Any number of Cree bulbs were ruined when people unscrewed them from the glass instead of the base, ending the life well ahead of it’s intended 25,000 hours. The next-gen 40W- and 60W-equivalent LED bulbs are considerably lighter and glass-free, opting instead for a translucent plastic. The plastic is slotted so heat can escape from the interior, which is important because there is less metal on the inside to conduct heat away from the LEDs. In fact there is no heat sink, a move that would have been a huge surprise 18 months ago, but seems logical after the release of Philips’ SlimStyle. The new Cree bulbs are omnidirectional and dimmable, as expected. The 4Flow 40W model (in 2700K) consumes 6W and produces 460 lumens, making for 77 lumens/watt. The new 60W operates at 11W and produces 815 lumens, according to Cree — that’s 74 lumens/watt. These numbers mark a drop in efficiency relatively to the previous 2700K units, which were at 75 lumens/watt and 84 lumens/watt respectively.

It’s not a major drop, but it’s not a move in the right direction. The logic here is likely Cree shooting to reduce manufacturing costs and willing to trade off a negligible amount of electricity usage (a few cents a month) in order to lower the price as much as possible. Another interesting move is that the warranty was dropped from ten years down to just three. This isn’t a major problem, as the number of people that return eight-year-old bulbs is limited, but the original point was to inspire confidence in consumers who were justifiably wary of newfangled solid-state lighting. Now that people have gotten used to using and seeing LED bulbs, Cree can lower the warranty and cut back on costs (or at least potential costs). and will be in Home Depot stores in November.This post is about my research into finding suitable MR16 LED’s for replacing the 50W recessed halogen lights in our house. In summary, I’ve found “ok” bulbs, not great bulbs, and you can read about the details below.

Our house is about 3 years old, new construction, and one of the many decisions we made during planning was recessed halogen vs. recessed LED lighting. At the time my calculations showed the additional cost for LED lights would only be recovered in electricity cost savings after about 12 years, not worth the cost at the time. Another problem was the optical quality of the products, the near halogen optical quality LED products were ridiculously expensive, and the mainstream LED’s were of poor optical quality, and had poor dimmability. Given the situation we opted for recessed Elco MR16 low voltage 12V AC magnetic transformer halogens, and planned on retrofitting them with LED’s as the technology improved and costs came down. Now, 3 years later; our electricity cost is way higher than originally estimated, we installed solar that gave us a 50% reduction in cost, some of the recessed reflectors are showing signs of heat damage from the halogen bulbs, and 12V MR16 LED’s have entered the mainstream.

I’ve been looking for MR16 LED’s for some time now, same problem as 3 years ago, dimmable good optical quality bulbs are very expensive, ~$20 per, while eBay and Amazon sourced Chinese manufactured no-name brands are ~$4. During my research I’ve made a few important observations: So what are my realistic choices: Here then is my review, more an exploration, greatly skewed by my subjective opinion vs. scientific fact, of the products I could find and test. I initially tested the bulbs by replacing the halogens in my office, but this quickly became cumbersome, so instead I created a test bed for evaluation, trying to simulate the various dimmer and transformer types available. I bought the the following items to match what I use in my house: Here are some pictures of the Elco enclosure, this will give you an idea of how to go about swapping the transformer, and how tight a squeeze it is: The DV-603P is a vanilly halogen and incandescent dimmer, it works just fine with the magnetic transformer and halogen bulbs in my house, but the MR16 LED manufacturer’s compatibility guide require the use of specific low voltage magnetic or electronic low voltage dimmers.

So I also bought: I considered a more elaborate test setup, but I don’t have access to the required equipment, and the measurements would be interesting from a scientific perspective, not so much a subjective perspective. So I opted for a simpler test setup, attached to a piece of hobby board, capturing waveforms using my Rigol DS4022 scope and a Rigol RP1050D high voltage differential probe and the UltraScope software. For transformers, I used the magnetic transformer from the Elco enclosure, and I bought three ELV’s from eBay, two from a known brand, and one unknown brand: For bulbs, I bought a variety of models from Amazon, eBay, and 1000bulbs: I tested the transformer response by monitoring the high voltage AC input and low voltage AC output sides using the oscilloscope. I controlled the ELV transformers using the ELV dimmer and the magnetic transformer using the magnetic dimmer. I attached a 12ohm resistor for a purely resistive load, the halogen bulb, and the Torchstar LED bulb.

I captured oscilloscope screenshots at full, half, and lowest dimming settings. Here are the results for the magnetic transformer: Here are the results for the HATCH RS12-60M-LED ELV transformer: Here are the results for the HATCH RL12-60A ELV transformer: Here are the results for the Advance Lite TC60W ELV transformer: Looking at the results we can see that the response waveforms for the halogen bulb is, not surprisingly, near that of the resistor. We can see that the magnetic transformer and LED load has all sorts of inductive goodness going on. And we can see that the RL12-60W and TC60W ELV transformers are not nearly as well behaved as the RS12-60M-LED ELV that is specifically designed for LED loads. I then proceeded to test the dimmability of the various LED bulbs, I summarize my subjective findings below: Magnetic: Good dimming range RS12-60M-LED: Good dimming range, slight transformer buzzing RL12-60A: Good dimming range TC60W: Good dimming range

Magnetic: Good dimming range, flicker at low end RS12-60M-LED: Limited dimming range, no flicker, slight transformer buzzing RL12-60A: Good dimming range, continuous flicker TC60W: Good dimming range, flicker at low end Magnetic: Good dimming range, flicker at low end, very loud transformer buzzing RS12-60M-LED: Good dimming range, flicker at low end, slight transformer buzzing Magnetic: Good dimming range, flicker at low end, slight transformer buzzing RS12-60M-LED: Good dimming range, slight transformer buzzing Magnetic: Good dimming range, switches off before end of dim range RS12-60M-LED: Good dimming range, slight transformer buzzing I was surprised that the cheap $3 eBay CREE COB MR16 LED bulbs worked as well as they did. Only downside is they switch off at around 20% when using the magnetic transformer, but dim down well. I don’t know if they really contain CREE COB LED’s, but the COB array arrangement of LED’s provide an even light source.