Focusable lens-Exchangeable Amphibious Transparent Light

[hanachan]

hi, all.
this project is a continuance of 'DIY SST-50 focusable U/W light'.
but ive changed & advanced its concept and now im building the parts
based on the new concept. so i make a new thread.

concept diagram

(clicking fig shows large one)

As shown in the figure, this light is a sort of 'modular light system'.
a newly added concept is separation of 'modify light path' part from
an emitter and this part is exchangeable as a lens in SLR.

actually im building a focusable light with transparent acrylic pipe.

this avoids vignetting of wide angle beam by opaque body tube.
my preliminary experiment showed the very tight and very wide beam
but a bit ugly lighting pattern on the wall. i think this is not issue in the real world.

i dont dive so frequently that i want to use the light both under water and on land.
Heat may be the main issue in its use on land. The acrylic pipe & box may
be soft by heat. this is why ive been building a light controller to monitor & control
the heat production. and ill use a junk CPU cooler on land.

depending on the progress, ill report the results.
but first i have to watch the world cup on TV for a while.
thank you.

 

[hanachan]

a plan of the light:

(clicking fig shows large one)

im now building the light-controller box.

(clicking fig shows large one)
it is a little difficult to build the box only with hand saw & drill.

 

[hanachan]

checking the connectivity between cooler part and controller box


a cooler & battery module temporally assembled:

most parts are made with aluminum plate or pipe.

 

[hanachan]

main components have been almost built.

but there are still a lot of things to do.

The circuit is fixed.


The PIC board previously built is a little bigger to be put in the control box.
ill redesign a new PIC board.

 

[wquiles]

The circuit is fixed.

With all of the work and effort that you are putting in this project, why are you using 14x of those not-so-great drivers to drive your SST-50? In my opinion it would be far easier to wire and significantly more efficient and robust to use a single H6CC driver from TaskLED that could drive your SST-50 up to a little bit over 6 Amps, in a true current regulated setup, that would give you far more flexibility on your battery pack choices, with the voltage for the pack being able to be up to about 25 volts :
http://www.taskled.com/h6cc.html

Just my 2 cents.

 

[hanachan]

Thank you for the informative comment. The reason i dont use a H6CC is simple.
i have already enough AMC7135 boards from DX and i know little about H6CC.

i doubt this light endures constant high power output of SST-50.
i use AMC7135 for the moment, i may replace it with H6CC after experimental use of the light.

 

[MrNaz]

Thank you for the informative comment. The reason i dont use a H6CC is simple.
i have already enough AMC7135 boards from DX and i know little about H6CC.

I strongly agree that using 14x AMC7135 is not a good setup for this light. You're putting a lot of effort into this, you really should use a good driver.

 

[hanachan]

thank you for the comment. MrNaz, you are right. but you may say nothing.
anyone wants to use a good driver. what driver do you recommend?
i think AMC7135 is not so good but not so bad.

i made 14x7135 regulator:

remove a diode and two AMC7135.


stack 4 AMC7135 boards


make the wire to battery(-) thicker with soldering


1) a center wire to batter+, 2) green wire to PWM, 3) black wire to LED-, 4) blue wire to batter(-). the wire 3 & 4 are thicker.

thank you.

 

[Walterk]

Wow!
At first it glance it looks 'quick and dirty' but you have eye for the details that matter.

 

[hanachan]

OMG, i did false wirings of left two AMC7135 boads.:sick2:
green wire->black, black->green are correct.
so i rewired them.

umh my products look always dirty regardless of their production speed.
thank you.

 

[hanachan]

as World cup ended i begin to do DIY.

i put the light control stuffs in the box somehow..

i must rewrite PIC program so the components can be disassemble.

not enough space:green:

themosensor1 is near LED, 2 is on aluminum base plate, 3 is for air temperature.

PWM is OK.

temperature values are not so stable but they can be used for monitor &
control the light output.

ill observe how much temperature rises.

thank you.

 

[Linger]

Thank-you Hanachan, for routinely putting out one-of-a-kind creations. Another carefully illustrated post. Thanx for sharing the building stages with us, it makes the final product even more imaginative.
I bet the acrylic sheet store loves you.

 

[hanachan]

Thank you, Linger.
im not sure the shop loves me but i love the shop because the shop sells
scraps of acrylic plates very cheaply 10kg 2000yen (about 20USD).
i could not build up my DIY housings without the shop.

BTW i observed the temperature change of this light. ill report the result.

Condition:
*room temperature: 26 degree C
*battery: 16850x4 para. full charged(4.2V no load)
*heat sink: SST-50->(a)
->alumi disk(30mm diameter,10mm thick)->(b)
->alumi plate(30x30mm,4mm thick) x2->(c)
->100x110x3mm alumi plate (base alumi plate).

thermal silicone glue (Sunhayato SCV-22) used at (b)
thermal compound from DX (sku13915) used at (a),(c)

*open circumstance (no lens pipe)


PIC works as follows (ver.LC08):
1) measure battery voltage->display
2) measure PIC board voltage (boost regulated 5V)->display
3) measure temperature near LED (T1) twice->display average
4) if the temp over 50 deg. C, PIC sets PWM 123/255.
5) measure temperature at base alumi plate (T2) twice->display average
6) measure air temperature in the box (T3) twice->display average
7) check PWM switch and up/down PWM
8) goto 1
this sequence is carried once/about 1sec.

i checked changes of voltages & temperatures every one min.

unfortunately the mini fan was disconnected. so no work of mini fan this time.
sometimes i also measured the temperature by the DMM.

Result:
i started the experiment with PWM=198/255(78%).

*the battery volatege changed relatively in wide range, for example 3.3-4.2volt. i think this is owing to PWM.
*PIC board voltage showed no change through the experment always 4.9Volt.

The temperatures measured were not stable, 1-3 deg.C easily changed.
the maximum temp. showed similar values measured by DMM. so i plotted it.

The temp. near LED (T1) rose rapidly. about 10 min T1 reached 50 deg C and
PIC set down PWM198->123(48%). after then T1 went down slightly and gradually rose again.

Alumi base plate temp (T2) showed similar rising curve as T1 with 4-5 deg C lower the T1.
after LED power down, it showed plateau at 47 deg C.

Air temp (T3) rose gradually from 27 to 38 deg C.

after 20min i powered off the light. the base alumi plate was very hot.
The acrylic box looked keeping its hardness.

The temp. measured by DMM:

The temp. near LED was about 4 deg C higher than T1.
The temp. at base plate was about 1-2 deg C higher than T2.
The air temp. was almost same as T3.

The temp. at top of the dome of SST-50 was 105 deg C.

Discussion:
the maximum temp measured by the thermosensor (LM35D National Semiconductor)
showed near value measured by DDM.

the discrepancy between temp. at near LED by DDM and LM35D may be due to
the fact that LM35D size is somewhat large so it was cooled by air around it.

Although roughly estimation, the thermo sensor can be used for monitoring.

i first knew the feeling of hotness by hand. 40 deg C is hot but keeping touch by hand.
50 deg C is too hot to touch by hand.

next ill check how much the CPU cooler prevents heating.

thank you.

 

[hanachan]

hi, ill report the effect of CPU cooler.

The base aluminum plate of the light box was attached to the cooler part at three points.


experiment setting

i measured also the temperatures at a (CPU cooler fin), b (base of battery box) and c (handle).

result:

the experiment conditions were same as previous one. ie full charged 18650x4 para, pwm=198/255
but the room air temp. was 28 degree C (2 deg higher than previous experiment).

T1 (near LED) reached at 40 deg C after 10min (50 deg C in the previous experiment) and gradually increased,
and after about 30min it deceased slightly due to drop of the battery voltage and finally increased to 45 deg C.

T2 (base aluminum) increased to 40deg C for 20 min. and kept its value.
T3 (air temp in the box) showed gradually increase curve and finally showed about 36 degree C.

the temp. of point a was 40 degree C (same as T2), b 39 deg C, c 30 deg C at end of experiment (after 60 min) respectively.

The CPU cooler worked better than i expected.

there may be some room to dissipate the heat to the handle.

next ill test under maximum power output of the light.

thank you.

 

[alpg88]

why not just get 1 sst50 der witchel driver?

IMO your entire project is way overcomplicated, but it is just my opinion, i wish you all the luck, keep us posted, i sure be curiously watching this thread

 

[hanachan]

Thank you for the comment, alpg88.
it is because i did not know the der witchel driver but now i know it.
ive read his thread briefly it sounds a nice driver but PWM may be somewhat difficult.

if you feel my project way overcomplicated, it may be because i do not know details of FET,
driver and a power LED well, so i did additional experiments and knew something new and changed
my specifications of the light, sorry.

BTW
ive checked the temperature change of the light driven at near max output (PWM=240/255, 94%).
the condition was same as previous test but the room air temperature was 30 degree C, two deg
higher than previous one.

result:


in this test the PWM up/down switch was always UP. so when T1 (near LED) reaches 50 deg.C
the PWM value is set 123 by the PIC automatically. after then as PWM switch is UP the PWM value increases
automatically up to 240 for about 10 sec. The Green arrow shows such an event. One arrow shows
one event (down to 123 and up to 240).

T1 reached to 40 deg.C at 3 min. (it took 7 min in previous test, PWM=198).
The maximum temp.s (T1,T2,T3) were 5 degree C higher than the previous test.
the PWM down & up occurred first 20min after beginning of experiment and
its incidence became gradually high. while the brightness of the light gradually
decreased, the temp. showed the tendency of plateau or slightly increase.

temperature at A(cooler fin), B(battery box base) & C(handle):
after 5min->ending temp.:
A: 35->42 deg C (very hot)
B: 30->40 deg C (hot)
C: 32->32 deg C (no change)

i measured the current at battery level by the DMM with SHORT, THICKER wires.
beginning: 4.7A, no load voltage:4.19V, ending: 3.3A, 3.83V respectively.

summary:
while the brightness decreased the temperatures did not decrease but slightly
increased, indicating the heat escape was insufficient. but i think the light
can be used on land within 1 hour at nearly maximal output as the cooler managed
to keep T1 under 50 deg.C.
for the moment the AMC7135 regulators may be sufficient for this light.

i found the fan of CPU cooler works with one 18650 battery (its spec needs 12volt)
so next i will check the fan effect.

thank you.

 

[Walterk]

Is the CPU-cooler ventilated to the outside air?
Or is it enclosed within a box?

 

[hanachan]

@Walterk
no ventilation nor enclosed. this time i first ventilated the CPU cooler.

fan effect test:
of course this junk heat pipe CPU cooler has a fun.


as i hate to use some power to the fun, i did not use it.
but the cooling effect was insufficient only with CPU cooler fin (T1 over 50 deg C).

while it is 12V fan, i found out it worked by only 1x18650 (4.1V)
and its current was very low (65mA). no sounds but the wind was very weak.
any way i tested its effect.

setting:


the fan was driven by isolated single 18650 (4.1V with no load) throughout the experiment.
other experiment conditions were same as the previous one expect for the room temperature (31 deg C).

result:

the translucent graph of the previous experiment is over written.

in spite of very weak wind of the fan its effect was remarkable.
the maximum of T1 (near LED) was kept under about 45 degC
so no work of power down program by PIC.

T1 and T2 showed decrement at the latter half period as the power of LED decreased and
T1 at end stage was lower about 10 degC than the previous one!

temperature at A(cooler fin), B(battery box base) & C(handle):
after 5min->ending temp.:
A: 30->(max 34)->32 deg C (not hot)
B: 29->32 deg C (not hot)
C: 29->31 deg C (not hot)

conclusion:
considering remarkable temp. down with low power waist, i had better use a cooler fan
even if it provides very weak wind rather than useing a big passive heat sink
...uuuh i must redesign the frame construction of the light.

brief summary from series of the experiments:
1) this thermo-sensor near LED shows about 5 deg C lower than by DDM thermo-sensor.
although the exact temperature of LED is not known, keeping T1 under 50 deg C
may guarantee the LED temp. under 70 deg C which is necessary for long survival of LED.

2) if the temp. of the base aluminum plate is under 40 deg C, T1 temp.
can be kept under 50 deg C. this implies that a heat sink is not necessary
under water unless i dive in the hot water bath 😀.

3) so a cooling system is thought which is attached on land and is released
under water. it is easy to say but the realization is difficult for considering
the connections among wire, switch and battery.

temporally i think
A) { 1) light path module + 2) light control module+ 3) heat sink module +
battery module}
+
B) { 4) heat fan module (including independent battery & switch)}

on land: use A+B
under water: use A

thank you for attention.

 

[hanachan]

hi,all. too hot to DIY in Japan.

An interim report:
1) after long waiting i got the DCDC converter (LDO06C) ordered in March!

i tested this.

a 330 ohm trim resistance resulted constant 4.2 volt output.

confirmed that the light can be controlled with varying AMC7135 Vdd voltage
(3W LED, input 8 volt (18650x2s), output 4.2V).
note that it wasted some power (0.64W in this case) with no light.

2) built a battery box for 2p3s 18650 for using the converter


3) built a frame which can include the battery box & the CPU cooler with fan


4) i found out a good alumi block sold as alumi dice (3x3x3cm).
i exchanged the alumi block under the LED with this.


im NOT sure that constant high output with LDO06C+AMC7135 is better than gradually decreasing output with only AMC7135.
ill examine which is better for me.

ive been rebuilding a simpler circuit (LC09 version).


FYI:
i bought sku 43043 99mm Replacement Glass Lens for Flashlights from DX.

but im disappointed. its not good. focal distance is about 140mm NOT 80mm as DX describes.

thank you.

 

[lucca brassi]

after long waiting i got the DCDC converter (LDO06C) ordered in March!

You have same problams like me ordering from DE :devil:

I like to warn you ..... main heatsink task is to cool semiconductor not to store heat , with such masive cube it is also difficult to adjust hysteresis (to wide)
(2'nd order regulation - overswing ) because of to long (correct) response of controllerand your error of regulation grow up.

If you want to work in that way I advice you to put under led 1/2'' plate of aluminium and then http://www.heatsink-guide.com/peltier.htm
and on hot side of peltier heatsink with fan ( but it need serious current) In that case you can regulate temperature much more efficient (FAST ) in software loop.
But much easier is to made split amplifier circuit as comparator with NTC . When NTC sense rise of temperature then send it to simple OP like 741 or something which controled
open FET which supply peltier. So you have power led almost on ''constant '' temperature in real time; not in minutes which is death for leds .
Look on led in same way as computer processor if heating don't work , thermal diode via MB-BIOS shut's down computer to prevent damage.
That's my opinion.

Just for second thoughts :tired: