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Discussion Starter · #1 ·
Just finished my copy of Achesalot's triple Seoul design, plugged it in, heard a very slight 'pop' and nothing. Did I just pooch the entire light? Any tips on trouble shooting would be appreciated!

I wired up the bFlex first, then shoved it inside the housing, then soldered the LED+/-, IN+/-, and SWA/B, so to take it apart means de-soldering a bunch of stuff... =(

What should I check first?

thanks for the help guys!

dave
 

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Asuming you have wired everything correctly then it sounds like the Bflex may have shorted on your housing and maybe popped a component.

check no shorts to the housing and all conections .

was there a flash from the leds , or just the pop from inside.

I had something touch my light housing and the lights did not work but it was not terminal gladly and worked later .
 

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Discussion Starter · #3 ·
Just a pop from the inside, no flash from the LEDs... Hopefully it's like yours and not terminal!

I'll pull it apart, and test it outside of the housing. I should probably take a break before I do something stupid (again)!

thanks,
dave
 

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I had a pop once. That was because I accidentaly reversed the polarity. I tought that I had destroyed the regulator. But It still works.

You say that you wired first and solderd second. Maybe something went wrong in the process? +/- leds and input reversed?
 

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Discussion Starter · #6 ·
Thanks for the tips guys! Before I rip everything apart, what kind of checks can I do, i.e with a multimeter?

Hey, just found one thing - when I check continuity across each LED, I guess the multimeter sends out a bit of current. Two of the LEDs glow a light blue, while the third does nothing. Could I have fried an LED? Or just coincidence that I got a bad one?

How often does one get a bad LED (SSC P4)? Or is this a sign of a short somewhere else?

Sorry if these questions are really basic - I'll be the first to admit that I'm not an expert in electrical details!

thanks,
dave
 

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When I built mine, I checked the continuity across the led's and found that it is dependent on the polarity (I too saw a faint glow). Try checking the "bad" led again with the multimeter leads both ways...Joe
 

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cdn-dave said:
Thanks for the tips guys! Before I rip everything apart, what kind of checks can I do, i.e with a multimeter?

Hey, just found one thing - when I check continuity across each LED, I guess the multimeter sends out a bit of current. Two of the LEDs glow a light blue, while the third does nothing. Could I have fried an LED? Or just coincidence that I got a bad one?

How often does one get a bad LED (SSC P4)? Or is this a sign of a short somewhere else?

Sorry if these questions are really basic - I'll be the first to admit that I'm not an expert in electrical details!

thanks,
dave
You should see them all light up if you have it all wired in series. That one could be bad, or it might be backwards. On CPF, they talked about how some SSCs were put on the starboard backwards. Check each individual LED just for fun.
 

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Discussion Starter · #9 ·
Yep, looks like I got a bad LED... I bypassed the middle one (bad one), hooked up power and voila, let there be light!! <insert groan here>

I saw that mentioned on CPF too, about how some SSCs were put on backwards. So would sending current through a LED backwards fry it?

Ah well, I'm glad the bFlex is okay and LEDs are cheap. Hmmm...maybe the new batches are out now???

thanks again for all the help!

dave
 

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cdn-dave said:
Thanks for the tips guys! Before I rip everything apart, what kind of checks can I do, i.e with a multimeter?

Hey, just found one thing - when I check continuity across each LED, I guess the multimeter sends out a bit of current. Two of the LEDs glow a light blue, while the third does nothing. Could I have fried an LED? Or just coincidence that I got a bad one?

How often does one get a bad LED (SSC P4)? Or is this a sign of a short somewhere else?

Sorry if these questions are really basic - I'll be the first to admit that I'm not an expert in electrical details!

thanks,
dave
if you check the continuity across the led with + on + mutimeter and - on - mutimeter, it will always work by lighting it with a little glow. I blow three circuits, one was with touching the housing and not heat shrink wrap or electrical tape it. another was overheat cause the resister to blow up inside the housing. if you wire leds in series on the led, one bad led will cause the whole setup not to light up. so take out the one bad led and recheck continuity across the whole series. check your voltage accross the input and output. if you have it apart, then check the current also.
 

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Discussion Starter · #11 ·
finished results!

So I let DX know what happened and they shipped me a replacement SSC asap! Just one piece - it took a couple weeks but I was out of town so no biggie.

I glued it on, wired it up, plugged it in and DOH! In my haste I put it on backwards! :madman:

Luckily it didn't do any damage, phew. I switched it around and finished it up. Here are a couple pics:

Floor Flooring Light Hardwood Grey
Floor Flooring Grey Hardwood Composite material

The only thing different that I did was use a couple spoke nipples for the hinge. I cut a couple old spokes to about an inch long, bent them into a J-shapes, and hooked them to holes I drilled just below the led mounting plate. The tricky part was glueing them in so they match up with holes in the outer angle plates.

In hindsite, I think I should've just stuck with a nut and plate or thru-rods. But, I was shooting for low weight and on my wife's baking scale (not very accurate), it comes up just under 120 grams! :thumbsup:

Pretty cool, thanks again to Achesalot for the design inspiration!

cheers,
dave
 

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Discussion Starter · #13 ·
Thanks achesalot!

I showed it to a bunch of my buddies and they all thought it was pretty cool too. This coming from a bunch of engineers, so hey, it's good stuff.

New problem now - I had it in my car for a few hours when it was really cold out (single digits, Fahrenheit), and now it doesn't work any more. When I test across each LED, it doesn't glow at all, like it used to. The battery still put out over 16 volts. Now what? Does cold affect LEDs? Any thoughts?

I should order a bunch more of the SSCs, maybe just to keep spares...

thanks,
dave
 

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Discussion Starter · #14 ·

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No way you damaged your LEDs by freezing them. Something must have come loose inside the light or your battery needs a thaw --my guess (the battery might read the volts but have no available current under any load). I'm looking at the SSC P4 spec and it says operating temp (-30 to +85 C) and storage temp (-40 to +100 C). You're well within that.

The thing you looked at (5 to 40C) / humidity less than 30% was talking about storing the emitters in those plastic packaging reels the LEDs come in when purchased in bulk.
 

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Discussion Starter · #16 ·
Phew, that's good news, thanks!

How can we explain the lack of glow when checking continuity across the LEDs? As Eddie commented:

eddielee70 said:
if you check the continuity across the led with + on + mutimeter and - on - mutimeter, it will always work by lighting it with a little glow.
I tried to check Amps across the battery, but came up with nothing. Am I doing this right? Multi metre on the + and - of the battery, and set to DC amps on the multi-metre. Should show up 4.4A, correct? Hate to think I have multiple issues with my setup...
 

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cdn-dave said:
:madman:

I think I know the answer: http://www.seoulsemicon.co.kr/_homepage/home_kor/product/spec/W42180.pdf

According to the above datasheet, it needs to be 5-40 degrees C. Darn Iowa cold snap... :madmax:

So, what's the best way to replace the LEDs? Pry off the entire star? Or can I pry off the emitter: http://www.dealextreme.com/details.dx/sku.2026

Looking forward to your advice...
you have to pry off the star. the emitter is very hard to take off the star. I try desolder emitter before, but doesn't want to come off. knife cutting doesn't work either. The continuity test might not work with your multimeter. I thought it's the norm for all multimeter, but it's not true with a friend's $50 multimeter. so test it out on a good working led first to see if yours lit up. on a another note, test all your new led that cames in. I was testing led by clamps and one of the brand new ssc led doesn't light. I went to test out 12 led DX sent me and two doesn't light the tiny glow. I email DX and they send replacement w/o asking. that tells you that DX knows some of the LED must fail during their star mounting process and didn't bother to test them before shipment. I burn out three leds, and they either would be (no glow but beeping continuity) or (no beeping continuity and no glow). The normal continuity test is no beeping, but tiny glow. depending on your multimeter as I have found out....
 

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cdn-dave said:
Phew, that's good news, thanks!

How can we explain the lack of glow when checking continuity across the LEDs? As Eddie commented:

I tried to check Amps across the battery, but came up with nothing. Am I doing this right? Multi metre on the + and - of the battery, and set to DC amps on the multi-metre. Should show up 4.4A, correct? Hate to think I have multiple issues with my setup...
sorry, dave, you can't check amp across battery unless connect through a open connection with a load. for example, to measure current, you unhook the positive wire to your setup and connect the +red to + of your battery and -black to your positive wire going to your setup, if you led lights up, then you should get a amp reading. 4.4A is current it can put out per hour, if the battery can put out that much w/o blowing. it's usually about 2C-3C depending on what kind of battery you have. I think you should check out this book from the library as I did to refresh my mind how voltage, current, resisters and capaciter work.

# Electronics for dummies
# McComb, Gordon.
# Hoboken, N.J. ; Chichester : Wiley, c2005.
 

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I'd say it probably depends on your multimeter as to whether you can make the LED glow with the continutity checker. Mine sure doesn't do that. The meter would have to be putting out at least the minimum forward voltage of the LED to light it. So your meter might light some LEDs that happen to have a lower Vf, but not others with a slightly higher Vf... it doesn't mean the LEDs are bad... just that Vf varies from LED to LED... and this is normal. For example.. I can take a CR123 battery and it will light some of my LEDs but not others... the others are not bad, they just have a forward voltage that is a little higher than the battery (3.27v). However, a single Li-Ion 18650 cell will light LEDs because it is 3.7v nominal (4.2v fully charged).

You can only check the Amps (current) with your meter in series. If placed between the battery and your light, it will show the current draw from your battery. No it will not show a 4.4A draw, that's the total AmpHour capacity of your battery. Assuming you have a 14.8v Li-Ion battery it would show about .75A on full power with a triple LED setup.

I have never had an LED fail on me. You'd have to do something pretty nasty to one to fry it... like apply 16v directly to the LED. I have had some bad ones that were dim or yellow to start with however. So if you guys really are damaging them, I wonder what you are doing... I don't think freezing them is going to kill them, in fact, most electronic components are much happier, the colder they are.
 

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Discussion Starter · #20 ·
Thanks for the Amp clarification and for the tip on the book - the title looks like it fits the bill!

I used to get the tiny glow with my multimeter. That's how I did the initial troubleshooting and which led to DX sending me one replacement, no questions asked. Everything worked fine afterwards, and I thought I was done - start riding!

Then I plug it in again to do the programming of the bFlex, and nothing. First thing, check voltage on the batteries - 16.1V. Next, check for a glow on the LEDs - nothing. I'll look for a small battery to verify - hopefully I didn't fine a way to fry the LEDs...

Will keep you posted, thanks again!
 
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