More JUNK from dealers

A month ago I ordered one of these as a test. If it was any good I would order more.

From here http://www.ebay.com/itm/360656430164

What I received was of good quality, and I used the star, heat sink and lens in my Mag Mod. Up until now, every MR16 bulb that I have ever seen had a constant current driver in it, and my test order bulb was no different. It had a nice driver in it.

All well and good, so I ordered 6 more. Even though between my 2 orders, 4 weeks apart, and the seller only sold 12 other bulbs during that time, I received bulbs that were of a completely different quality, as though they all came from a different manufacturer.

I think that is the 2 that GarryBunk ordered 2 days after I did, 2 rows above my first order. :wink:

To me this means that a seller such as this one does not have stock on hand, but rather takes orders and then fills them from a supplier.
Here are pics of the total crap that I received on the second order. I will comment on what I see above each pic.

First pic, the lens has been removed. I wrote “11.4” on the star as that is the voltage across the 3 emitters that are wired in series. Up until now there was only 9.4V (different emitters) because the CC driver in the base limited the current to 300mA. This bulb is supposed to be drivin at 3W and the voltage and current readings of the first bulb I ordered verify that. Also the lead wires are soldered to the wrong place, very poorly I might add. They should have been soldered to those 2 unused tabs towards the middle of the star. Electrically it is the same, but by soldering directly to the emitter, the joint is disturbed. More on that later.

The applying of the thermal compound is so poorly done that it is almost comical.

I removed the star, looks like none ever touched the heat sink.

The “driver”, just a full wave bridge and some current limiting resistors. Resistors are a cheap and crude way of imitating a current driver. At 12V in there is 110mA flowing through the 3 emitters for about 1.2W (not 3W as claimed)

No capacitor on the back side of the “driver” That is because if 12V AC was the input, the voltage would rise to the peak value of the sine wave, or 1.414 x 12 = 17. If there was a for real CC drive, as there should be, that would be OK. In the case of the resistors, the current would rise above the 300mA level and blow the LED’s

Having said that, these next pics will show that it wouldn’t matter anyway. These bulbs are going to blow anyway
None of the LED’s touch the star! There are air gaps between every one of them. This is due in part to the first pic where the lead wires are soldered to the wrong place. In doing this, the emitter lead is disturbed and the LED lifts off the star.



I must add, that in this case the seller is as much a victim as I am. Because I believe that he does not keep stock on hand, he only relays what he gets from his order. Who could possibly check each batch. I only realized how bad these bulbs actually are because I took them apart to use the parts separately. I bought 6 and took apart 3. All 3 are as described above. I would estimate that they would probably blow within 15 seconds of connecting them to a 12V source.

I’ve run into the same thing buying the typical 9w LED 120VAC bulbs from Aliexpress. I purchased from the same seller three times and each batch came in constructed differently. Like you I made a small initial order to check out the quality. I was more fortunate though in that my second large order was even better than the first. A third large order was worse quality than the first.

1st order: Tiny dabs of paste between the star and heat sink. Star was screwed down with a single screw way on the edge of the star and it was not even flat (very little contact)
2nd order: This was the good one. They had used a thermal epoxy to fasten the star with good protrusion around the edges. A single screw was used in the middle to reduce the gap as much as possible.
3rd order: No heat sink paste at all. Screw was in the middle of the star.

After fixing the heat sink paste issues my bulbs have been used regularly for months with no issues. They have the same type of LEDs as on yours but are 3w each. The gap under the diodes is scary!

Wow! You're right, it is almost comical! And people wonder why we use the term "Made In China" (or M.I.C.) as an insult!

I need to start a thread on getting these MR16 bulbs into one of those flashlights that you get with the cordless drill combo kits (I just got another one). The MR16 bulb is way smaller than the two I have.

-Garry

You will NOT be able to use this light as is. There is no CC driver in it, 18V will be too high. Could you check those bulbs you got. I would like to know if you received the same CC driver that I did on my first order. That light could be run at up to 24V

I understand the bulb your posting about here couldn't be used in an 18v flashlight, I meant the "good" ones.

I'll try to take a peek at mine soon, though not sure when I'll get to it.

-Garry

Ok got a couple mins to tear both mine apart (breaking one TIR tab in the process). Looks like both mine have the "good" driver. Both have stars thermal pasted to the aluminum disk, but no paste under the disk to the heatsink.

Pics:

Best I could do with quick pics from my phone.

-Garry

That driver even has a sense resistor with and extra set of bare pads in case you want to bump up the drive current. You could get away with a little bit more, as it is set to 300mA now. This light was intended to run 24/7 but in a flashlight you could probably get away with a little higher current as the runs will be shorter.

I need to refresh myself on the procedure from the other thread (3D Mag MR16), but aren't I eliminating that driver altogether, rewiring the emitters in parallel, then direct driving the emitters from 3 alkaline D cells? (And I'm replacing those emitters with the FT Bridgelux ones.)

-Garry

Yes, if you put it in a Mag Lite. We were also talking about putting it in a cordless drill flashlight. With the “good” drvier you could put it in, as is, in any 12-24V light. THEN, you may want to do the resistor mod on the driver.

Ah, gotcha. I was mixing up topics. These first ones I got were intended for 3D Maglites.

-Garry