4 MC-E Video Head

[Delphinus]

I converted one Scubalight Modular Head 6x3W Led to 4xMC-E and it worked more or less OK but the MC-E have a behavior that I never noticed in other led, when I turn on the power I get an X value in lumens but it start to decrease fast and after some minutes it stabilize, I’m using MC-E stars and copper dissipater.
All indicates a heat problem because to accelerate the cure of the artic silver that I use to glue the stars to the copper I turn the power on while touching a led and it became very hot with the copper cold.
I never felt any heat in the front of a led using the same combination, this is normal for a MC-E?
Besides this the lamp works very well but after the warm period the Lumens came down about 9%

 

[Codiak]

I converted one Scubalight Modular Head 6x3W Led to 4xMC-E and it worked more or less OK but the MC-E have a behavior that I never noticed in other led, when I turn on the power I get an X value in lumens but it start to decrease fast and after some minutes it stabilize, I’m using MC-E stars and copper dissipater.
All indicates a heat problem because to accelerate the cure of the artic silver that I use to glue the stars to the copper I turn the power on while touching a led and it became very hot with the copper cold.
I never felt any heat in the front of a led using the same combination, this is normal for a MC-E?
Besides this the lamp works very well but after the warm period the Lumens came down about 9%

I noticed the same behavior on an SST-90 driven with a hipCC at 2.8A
Turned out to be the sinking of the driver was the issue, not the star

 

[Delphinus]

I noticed the same behavior on an SST-90 driven with a hipCC at 2.8A
Turned out to be the sinking of the driver was the issue, not the star

In my case it happens when I use the driver and my lab power supply so it must be the star or the led.

Here do you get your SST-90 I would like to try them.

 

[350xfire]

In my case it happens when I use the driver and my lab power supply so it must be the star or the led.

Here do you get your SST-90 I would like to try them.

sst-90 get them through avnet.com.. You may want the SSR version mounted on star.

 

[Codiak]

sst-90 get them through avnet.com.. You may want the SSR version mounted on star.

avnet or photonfanatic

 

[H20doctor]

seems when I fire up a MCE with a 3.7 volt 18650 ... they get Hot quick !! might be a driver issue if your not getting Blinded and your eyes scorched by the chip... MCE chips are a great Led , and put out some great light..

 

[Codiak]

seems when I fire up a MCE with a 3.7 volt 18650 ... they get Hot quick !! might be a driver issue if your not getting Blinded and your eyes scorched by the chip... MCE chips are a great Led , and put out some great light..

I'm stuggling with the cost of the MCEs vs the SSR-50 and asking myself why not just use the 50's

 

[Delphinus]

If you are like me and enjoy pictures here are some and a brief description.

I planned to build 4 small heads to group in 2 but because I don’t have enough time to complete it before vacations I modified one Scubalight 6 Led

I used 2 MC-E M Star 752lm and 2 MC-E K Warm Star 650lm, I’m still waiting for an order from DealExtreme so I had to use the drivers that I had, I used 5 drivers, 3 per Die so one die is off.

The drivers are 4x670mA and one 1x970mA adjusted to 670mA.

What could be changed, the battery, it’s a 13.2V 4Ah NiMh with it the autonomy is 90’ that will do for 2 dives but 5x670mA=3,35A so 90’ mean that I can only drain 2,65A from the batteries so it won’t work at full power.

So if I had more time I should use 4 drivers at 970mA one per led driving each Die at 485mA that will not stress the battery and will gave 120’

I made a Alu spacer in case I decide to do not use lens probably I won’t because the collimator that I have doesn’t give a smooth light.
Without the collimator at 1 meter I measure 870 Lux and with 1 Kathod L50040WK2WP 4Led 40 degree 3200 Lux.

The pictures

Original board and colimator

Coller and spacer

Drivers

Back

Front

 

[SUBjohan]

Without the collimator at 1 meter I measure 870 Lumens and with 1 Kathod L50040WK2WP 4Led 40 degree 3200 Lumens.

I think/hope you mean lux not lumen.

Greetz Johan

 

[Delphinus]

I think/hope you mean lux not lumen.

Greetz Johan

You are correct tanks :candle:

I already changed the post.

 

[Hallmcc]

All indicates a heat problem because to accelerate the cure of the artic silver that I use to glue the stars to the copper I turn the power on while touching a led and it became very hot with the copper cold.

Are you saying that the copper heat sink is staying cold to the touch? If so that is a big problem. Second issue that I wonder about is the heat shrink over each driver. If it is trapping heat then something is going to go :poof:

 

[Delphinus]

Are you saying that the copper heat sink is staying cold to the touch? If so that is a big problem. Second issue that I wonder about is the heat shrink over each driver. If it is trapping heat then something is going to go :poof:

The copper heat shink doesn't stay cold but about 30ºC lower that the center of the led.

In the air and after 60'' the center of the copper gave me 60ºC and the center of one led 90ºC, there is no reason to worry because even I’m in Maldives with 30ºC underwater that means that the led’s will operate at 60ºC.
It was my first time using the MC-E, I assume that the aluminum stars can't dissipate some much heat fast enough.

In the last six years the led’s increase in power but the stars remain without much evolution, next time I will try the MC-E without star.

 

[350xfire]

I use MCE with star and house it in a 2" aluminum head with MR11 reflector. After 1 hour run time outside of water I get about 75C at the LED and about 65 on the outside of the head. My head gets warm all the way through and the temp difference is about 10-15c.

 

[Delphinus]

I use MCE with star and house it in a 2" aluminum head with MR11 reflector. After 1 hour run time outside of water I get about 75C at the LED and about 65 on the outside of the head. My head gets warm all the way through and the temp difference is about 10-15c.

In that case apparently my stars aren’t OK or the values that I got are not precise, I will make more tests with a different thermometer, today I used an infrared and it’s possible that it can’t measure accurately when the led is on.

It’s also important to refer that I measure the center of the led and not the surface of the star.

 

[Delphinus]

Yesterday I made a test, well more a partial one I forgot the slate to adjust the white balance and also my dry suit, but here are 2 small videos of the same subject.

http://www.miguelamar.com/UW/VIDEO/Sesimbra/sabela_1.mp4

http://www.miguelamar.com/UW/VIDEO/Sesimbra/sabela_3.mp4

Next time I also need to do not film the lights :)

 

[Packhorse]

Looking good.

How does it go further away from the subject?

 

[Delphinus]

Looking good.

How does it go further away from the subject?

I didn't use any lens but for film or photo I would say about 35-45 cm and that's very good since even with a couple of 300W strobes we can't get the colors in photo longer then 150-180 cm.

I couldn't came to a conclusion about the color since I forgot the white slate but I would like to experiment a head with the cold led’s without lens and the warm with them that way I will get daylight at close range and project the lower Kelvin.