LEDs

[Hilton]

Hi,

Seems like it is a no-brainer (and easy) for pilots to use LEDs in various
forms. Why then, do miners not use them? Why do those trapped miners only
have a few hours of light available? Heck, the mine companies could buy al
cheapo LEDs for nothing and spread them throughout the mine for little to no
cost. These are give away items now. One single tiny little LED would be
invaluable right about now and last forever.

Some things just don't make sense.

Hilton

[Larry Dighera]

On Thu, 9 Aug 2007 16:40:44 -0700, "Hilton" > wrote
in >:

>One single tiny little LED would be invaluable right about now and last forever.

And they are cheap too:
http://www.surpluscomputers.com/store/main.aspx?p=SearchBody&search=flashlight

[[email protected]]

On Aug 9, 5:40 pm, "Hilton" > wrote:
> Hi,
>
> Seems like it is a no-brainer (and easy) for pilots to use LEDs in various
> forms. Why then, do miners not use them? Why do those trapped miners only
> have a few hours of light available? Heck, the mine companies could buy al
> cheapo LEDs for nothing and spread them throughout the mine for little to no
> cost. These are give away items now. One single tiny little LED would be
> invaluable right about now and last forever.
>
> Some things just don't make sense.
>
> Hilton

Everything that goes into a mine has to pass the explosion proof test
requirements. LEDs can pass, but it has to be in a tested design.
That adds cost...

Dean

[[email protected]]

wrote:
> On Aug 9, 5:40 pm, "Hilton" > wrote:
> > Hi,
> >
> > Seems like it is a no-brainer (and easy) for pilots to use LEDs in various
> > forms. Why then, do miners not use them? Why do those trapped miners only
> > have a few hours of light available? Heck, the mine companies could buy al
> > cheapo LEDs for nothing and spread them throughout the mine for little to no
> > cost. These are give away items now. One single tiny little LED would be
> > invaluable right about now and last forever.
> >
> > Some things just don't make sense.
> >
> > Hilton

> Everything that goes into a mine has to pass the explosion proof test
> requirements. LEDs can pass, but it has to be in a tested design.
> That adds cost...

Plus mines are already required to have emergency lights.

But another question arises, how do you find the "tiny little LED" in
a dark mine?

--
Jim Pennino

Remove .spam.sux to reply.

[Morgans[_2_]]

<deanwil> wrote
>
> Everything that goes into a mine has to pass the explosion proof test
> requirements. LEDs can pass, but it has to be in a tested design.
> That adds cost...

True, but that seems like a good product that needs to be developed.

If it were me, I would want 3 - 3 watt LED's, in a head lamp with the
typical wire going to a belt battery pack with 6 or 7 C-NiMH cells. Two
switches, or one three position switch - one to light only one LED, and one
to light all three. That has to be a lot more light than what ever they are
using.

It sounds like a product to develop, wouldn't you think? It would be a
piece of cake for you.
--
Jim in NC

[Bob Fry]

>>>>> "j" == jimp > writes:

j> But another question arises, how do you find the "tiny little
j> LED" in a dark mine?

I keep these on keychains:
http://www.photonlight.com/X-Light-Micro-Keychain-LED-Flashlights-p/xm-keychain-led-flashlight.htm
--
I think college administrators should encourage students to
urinate on walls and bushes, because then when students from
another college come sniffing around, they'll know this is
someone else's territory.
- Jack Handey

[Hilton]

> But another question arises, how do you find the "tiny little LED" in
> a dark mine?

My fire detectors in my house have a little 9V battery and those LEDs flash
for many months. Flip a switch and a tiny LED could shine for weeks.

To answer Dean's question, it has to be really easy to pass the 'explosion'
test for LEDs - again, this is from someone who just 'plays' with LEDs as a
hobby. But the 'working bit' is exclosed in a tough plastic unlike those
flash lights although I'm sure they are ruggadized. Perhaps the best bet
would be to many a really tiny headlamp and put it on a canary.

I think an hour's thinking could come up with many options, each one better
that the situation we have now with six (hopefully alive) miners in 58F
temperatures in darkness.

Oh well, just a thought.

Hilton

[Ben Jeffrey]

It's been done.
http://www.intrinsically-safe-instruments.com/intrinsically-safe-flashlight.html


Ben Jeffrey


"Hilton" > wrote in message
...
> Hi,
>
> Seems like it is a no-brainer (and easy) for pilots to use LEDs in various
> forms. Why then, do miners not use them? Why do those trapped miners
> only have a few hours of light available? Heck, the mine companies could
> buy al cheapo LEDs for nothing and spread them throughout the mine for
> little to no cost. These are give away items now. One single tiny little
> LED would be invaluable right about now and last forever.
>
> Some things just don't make sense.
>
> Hilton
>
>

[[email protected]]

On Aug 10, 8:40 am, Clark > wrote:
> wrote groups.com:
>
>
>
>
>
> > On Aug 9, 5:40 pm, "Hilton" > wrote:
> >> Hi,
>
> >> Seems like it is a no-brainer (and easy) for pilots to use LEDs in
> >> various forms. Why then, do miners not use them? Why do those trapped
> >> miners only have a few hours of light available? Heck, the mine
> >> companies could buy al cheapo LEDs for nothing and spread them
> >> throughout the mine for little to no cost. These are give away items
> >> now. One single tiny little LED would be invaluable right about now
> >> and last forever.
>
> >> Some things just don't make sense.
>
> >> Hilton
>
> > Everything that goes into a mine has to pass the explosion proof test
> > requirements. LEDs can pass, but it has to be in a tested design.
> > That adds cost...
>
> With low voltage systems it's fairly easy to meet the requirements for
> hazardous area ops. IIRC anything below 5 volts is considered safe.
>
> --
> ---
> there should be a "sig" here- Hide quoted text -
>
> - Show quoted text -

It's not just voltage. The housing has to be able to contain an
explosion inside of it without igniting combustible gases in the
surrounding air...

Dean

[[email protected]]

Clark > wrote:
> wrote in
> oups.com:

> > On Aug 10, 8:40 am, Clark > wrote:
> >> wrote
> >> groups.com:
> >>
> >>
> >>
> >>
> >>
> >> > On Aug 9, 5:40 pm, "Hilton" > wrote:
> >> >> Hi,
> >>
> >> >> Seems like it is a no-brainer (and easy) for pilots to use LEDs in
> >> >> various forms. Why then, do miners not use them? Why do those
> >> >> trapped miners only have a few hours of light available? Heck, the
> >> >> mine companies could buy al cheapo LEDs for nothing and spread them
> >> >> throughout the mine for little to no cost. These are give away
> >> >> items now. One single tiny little LED would be invaluable right
> >> >> about now and last forever.
> >>
> >> >> Some things just don't make sense.
> >>
> >> >> Hilton
> >>
> >> > Everything that goes into a mine has to pass the explosion proof test
> >> > requirements. LEDs can pass, but it has to be in a tested design.
> >> > That adds cost...
> >>
> >> With low voltage systems it's fairly easy to meet the requirements for
> >> hazardous area ops. IIRC anything below 5 volts is considered safe.
> >>
> >> --
> >> ---
> >> there should be a "sig" here- Hide quoted text -
> >>
> >> - Show quoted text -
> >
> > It's not just voltage. The housing has to be able to contain an
> > explosion inside of it without igniting combustible gases in the
> > surrounding air...
> >
> That requirement goes away on intrinsically safe devices.

> --
> ---
> there should be a "sig" here

Actually the requirment is that the device be sealed such that explosive
gases can't get inside where any sparks from the switch turning the
device on and off might ignite them.

--
Jim Pennino

Remove .spam.sux to reply.

[[email protected]]

Clark > wrote:
> wrote in :

> > Clark > wrote:
> >> wrote in
> >> oups.com:
> >
> >> > On Aug 10, 8:40 am, Clark > wrote:
> >> >> wrote
> >> >> groups.com:
> >> >>
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> > On Aug 9, 5:40 pm, "Hilton" > wrote:
> >> >> >> Hi,
> >> >>
> >> >> >> Seems like it is a no-brainer (and easy) for pilots to use LEDs in
> >> >> >> various forms. Why then, do miners not use them? Why do those
> >> >> >> trapped miners only have a few hours of light available? Heck,
> the
> >> >> >> mine companies could buy al cheapo LEDs for nothing and spread
> them
> >> >> >> throughout the mine for little to no cost. These are give away
> >> >> >> items now. One single tiny little LED would be invaluable right
> >> >> >> about now and last forever.
> >> >>
> >> >> >> Some things just don't make sense.
> >> >>
> >> >> >> Hilton
> >> >>
> >> >> > Everything that goes into a mine has to pass the explosion proof
> test
> >> >> > requirements. LEDs can pass, but it has to be in a tested design.
> >> >> > That adds cost...
> >> >>
> >> >> With low voltage systems it's fairly easy to meet the requirements
> for
> >> >> hazardous area ops. IIRC anything below 5 volts is considered safe.
> >> >>
> >> >> --
> >> >> ---
> >> >> there should be a "sig" here- Hide quoted text -
> >> >>
> >> >> - Show quoted text -
> >> >
> >> > It's not just voltage. The housing has to be able to contain an
> >> > explosion inside of it without igniting combustible gases in the
> >> > surrounding air...
> >> >
> >> That requirement goes away on intrinsically safe devices.
> >
> >> --
> >> ---
> >> there should be a "sig" here
> >
> > Actually the requirment is that the device be sealed such that explosive
> > gases can't get inside where any sparks from the switch turning the
> > device on and off might ignite them.
> >
> I don't believe that is correct. Perhaps a mechanical switch might require
> a seal but it might not on a low voltage system. In general an
> intrinsically safe device does not require a seal for explosion hazard
> mitigation. Other factors such as desire to exclude moisture might result
> in a sealed case.

The voltage is irrelevant; sparks are sparks.

Have you ever actually seen a flashlight approved for use in explosive
environments?

They are nothing more than a rubber covered flashlight with rubber
seals on everything and a rubber cover over the switch.


--
Jim Pennino

Remove .spam.sux to reply.

[Jackal24]

wrote in :


> But another question arises, how do you find the "tiny little LED" in
> a dark mine?
>

A tiny little light will go a long way if there is absolutely no ambient
light.