Huh? Bombproof X5 isn't.

[PlayboyJoeShmoe]

Small boy was bothering with lights on my desk. I figured X5 was as safe a light as I had there.

He couldn't push the button so I did.

Only 4 of the 5 LEDs light up. 1 has gone dark.

Who'da thunk it?

 

[PhantomPhoton]

How old is it? Doesn't surprise me if it's an older model with BS's etc. 5mm LEDs do die off eventually.
At least Inova will replace it for ya if you feel the need.

 

[Mockingbird]

This probably isn't the cause of the problem, but you might check the batteries. Maybe there is enough voltage to light 4, but not all five LEDs. You never know.

 

[eeagle7]

This probably isn't the cause of the problem, but you might check the batteries. Maybe there is enough voltage to light 4, but not all five LEDs. You never know.

Interestingly I have found freshly charged RCR123's in my X5 will cause only 4 LEDs to light....after the batteries drop slightly in voltage all 5 LED again light as normal.

 

[kramer5150]

Pretty darn close though, given its popularity and lengthy production run. Just send it back to Inova under RMA.

 

[Kiessling]

I had an X5 in my car for a few years and now only 3-4 LEDs light up, when I shake it, I sometimes get 5. With mine, it is a contact issue in the sealed part of the light.
bernie

 

[MWClint]

Interestingly I have found freshly charged RCR123's in my X5 will cause only 4 LEDs to light....after the batteries drop slightly in voltage all 5 LED again light as normal.

when overdriving 5mm leds that are in parallel, the vf's can be become
mismatched and the led with the highest vf may not light up.
the low vf leds are sucking up extra current..causing a large voltage drop that
ends up starving that one led.

Small boy was bothering with lights on my desk. I figured X5 was as safe a light as I had there.

He couldn't push the button so I did.

Only 4 of the 5 LEDs light up. 1 has gone dark.

Who'da thunk it?

same thing.. batteries are too drained to feed the led with the highest vf..
change the batteries and i will bet it'll work again.

 

[woodrow]

Maybe its a good thing...if the X5 runs for a million years on 2xdead 123a's powering 5 leds....imagine how long it could run powering 4 or three

 

[MichaelW]

If all five are still working [white X5] but are really dim, would Inova replace it.

 

[PlayboyJoeShmoe]

This light is one I got in a lot of "X" lights not more than a couple months ago.

Hasn't had near the kind of use to kill the batteries but they will be checked once I've finished with my user cp threads.

 

[Illum]

Assuming inova still stuck with Nichia CSs...

yeah, it might be burnt out. My X5 measures 200ma +/- 10ma from the Tail...which equates to about ~38-40ma per LED...quite high...

1xRCR123A and only 4 LEDs might just a sloppy gate/Vf issue

I had an X5 in my car for a few years and now only 3-4 LEDs light up, when I shake it, I sometimes get 5. With mine, it is a contact issue in the sealed part of the light.
bernie

too big of a hassle to return it huh

 

[PlayboyJoeShmoe]

Hassle for sure!

I did not check the batteries yet, but I shall.

 

[Outdoors Fanatic]

That's just a dead 5mm LED, it has nothing to do with the legendary toughness of the X5.

 

[PlayboyJoeShmoe]

Still QUITE annoying however...

Will be home eventually and check the batteries.

 

[PlayboyJoeShmoe]

The batteries show a bit over 3fA (flash amps) so I think that is not the problem.

Tries one other thing....

Neither wacking it nor two RCR123 get that other LED to light up.

I could call Inova. I have the number in my cell. I'm just not sure it's worth the hassle.

 

[zipplet]

Regarding checking the batteries I'd wager it has more to do with the voltage of the cells rather than flash amps - but if they manage 3 flash amps the voltage is probably high enough.

I've had a couple of 5mm's die in chinese cluster lights like that. Wouldn't expect it from Inova though - but this isn't a slur against them, bad 5mm LEDs happen even if you buy premium nichias :shakehead

 

[sORe-EyEz]

not that my X5T is used that often, but mine just dims evenly till its weaker than LED indicator diodes on my PC.

 

[funkychateau]

when overdriving 5mm leds that are in parallel, the vf's can be become
mismatched and the led with the highest vf may not light up.
the low vf leds are sucking up extra current..causing a large voltage drop that
ends up starving that one led.

I don't understand that.

If several LEDs are wired in parallel, the same voltage is applied to all. If they all light up at low current, how does driving the combo at higher bias reduce the voltage applied to any individual LED? Whatever the voltage applied to the combo, wouldn't it be higher when overdriven than when not?

If that is the case, I would think it unusual to see one LED lose drive as the voltage across all increases in unison.

I can imagine one mismatched (high Vf) LED in a parallel string being always underdriven, but it's a bigger leap to imagine them all working OK at low bias and then one turning off at a higher applied forward voltage.

 

[PlayboyJoeShmoe]

I do know from the wet finger test that the X5 is direct drive.

My wet finger got 4 Leds to light slightly.

I have a somewhat older silver X5 here somewhere... got it and it works fine. It even works on the power of just one 123.

EDIT: For that matter the black one lights up 4 LEDS with one 123.