Need help wiring bike light, please.

"Lewis Campbell" wrote: (clip) I am trying to find a place to buy a zener
diode for my genetrator (clip)
^^^^^^^^^^^^^^^^
First off, the problem may not be the zener diode. An intermittent problem
like this can be something as simple as a loose connection, or an
tough-to-isolate-and-repair fault inside the generator itself. To work on
this you should have a volt-ohm meter, and a basic understanding of simple
circuits. Intermittent problems are the hardest, because they come and go,
so 1.) You don't always have a symptom to look for, and 2.) You're never
sure it is fixed.

You may be able to find the problem by wiggling things while you crank.
Good luck.

On 26 Aug 2004 08:55:59 -0700, [email hidden] (Lewis Campbell)

Quoted message said:

Okay, my knickname is NOT Sparky and I am an electrical DUNCE. :-)

I am trying to find a place to buy a zener diode for my generator (6V
3W) powered head & tail lights.

The current headlight has a diode with the following info on it:-

ST B7W 04 6V4B C310 (I have NO idea what this means)

I think there may be something wrong with this one as the lights
occasionally go out for, as far as I can see, no apparent reason.

I would appreciate it if someone could throw me a bone here, or point
me in the right direction.

First, are you sure it's a diode, and second, are you sure it's a
Zener diode? Where and how is it placed in the circuit? Generator
lighting systems usually don't try to rectify the current; they just
use the AC output and leave it at that. I have seen a capacitor
across the base of the bulb on one or two occasions, but a failure in
that part should not take out the bulb unless it went to a dead short,
which is possible but unlikely, and which also seldom corrects itself.

--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Lewis Campbell said:

I would appreciate it if someone could throw me a bone here, or point
me in the right direction.

I can point you in the right direction.
www.topica.com/lists/bikecurrent/read

Unfortunately Topica search engine seems to be out of shape at the moment,
but join the list and ask there. There is nothing in the world of bicycle
lighting that cannot be answered on that list.

--
Perre

You have to be smarter than a robot to reply.

(Lewis Campbell) said:

Okay, my knickname is NOT Sparky and I am an electrical DUNCE. :-)

I am trying to find a place to buy a zener diode for my generator (6V
3W) powered head & tail lights.

The current headlight has a diode with the following info on it:-

ST B7W 04 6V4B C310 (I have NO idea what this means)

It is not quite a zener:

ST = manufacturer - ST Microelectronics
BZW = zener/transient suppresor
04 = 400 watts pulse power dissipation
6V4B = 6 volt, bidirectional

Unfortunately, most places that sell these things have a minnimum
order of around 20 bucks or they charge a handling surcharge, so if
this is really what is wrong it may be cheaper to figure out a
work-around.

(Lewis Campbell) said:

Okay, my knickname is NOT Sparky and I am an electrical DUNCE. :-)

I am trying to find a place to buy a zener diode for my generator (6V
3W) powered head & tail lights.

The current headlight has a diode with the following info on it:-

ST B7W 04 6V4B C310 (I have NO idea what this means)

It is not quite a zener:

ST = manufacturer - ST Microelectronics
BZW = zener/transient suppresor
04 = 400 watts pulse power dissipation
6V4B = 6 volt, bidirectional

Unfortunately, most places that sell these things have a minnimum
order of around 20 bucks or they charge a handling surcharge, so if
this is really what is wrong it may be cheaper to figure out a
work-around.

On 26 Aug 2004 12:34:35 -0500, Jim Smith <[email hidden]>

Quoted message said:

(Lewis Campbell) said:

Okay, my knickname is NOT Sparky and I am an electrical DUNCE. :-)

I am trying to find a place to buy a zener diode for my generator (6V
3W) powered head & tail lights.

The current headlight has a diode with the following info on it:-

ST B7W 04 6V4B C310 (I have NO idea what this means)

It is not quite a zener:

ST = manufacturer - ST Microelectronics
BZW = zener/transient suppresor
04 = 400 watts pulse power dissipation
6V4B = 6 volt, bidirectional

Unfortunately, most places that sell these things have a minnimum
order of around 20 bucks or they charge a handling surcharge, so if
this is really what is wrong it may be cheaper to figure out a
work-around.

Looks like they're just using it as a safety limiter to protect the
bulb, then; that's all you can really accomplish with one of these.
They're analogous to a fuse in operation, in a way; once they blow,
they *stay* blown.

I'd desolder one end and see what happens. (In fact, if it were me,
I'd just dike it out and leave it gone unless that bulb's an expensive
and hard-to-get bugger.)
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.

Werehatrack said:

Looks like they're just using it as a safety limiter to protect the
bulb, then; that's all you can really accomplish with one of these.
They're analogous to a fuse in operation, in a way; once they blow,
they *stay* blown.

This isn't one of those. It is basically two zeners in parallel one
pointed each direction.

Quoted message said:

I'd desolder one end and see what happens. (In fact, if it were me,
I'd just dike it out and leave it gone unless that bulb's an expensive
and hard-to-get bugger.)

That is what I would do too.

A workable substitute could be had by getting two 6.3 volt zeners and
connecting those in parallel in opposite directions. Radio shack might
sell those.

Jim Smith said:

Werehatrack said:

Looks like they're just using it as a safety limiter to protect the
bulb, then; that's all you can really accomplish with one of these.
They're analogous to a fuse in operation, in a way; once they blow,
they *stay* blown.

This isn't one of those. It is basically two zeners in parallel one
pointed each direction.

Quoted message said:

I'd desolder one end and see what happens. (In fact, if it were me,
I'd just dike it out and leave it gone unless that bulb's an expensive
and hard-to-get bugger.)

That is what I would do too.

A workable substitute could be had by getting two 6.3 volt zeners and
connecting those in parallel in opposite directions. Radio shack might
sell those.

Oops! I meant to say "series." Please replace both instances of the
word "parallel" above with the word "series."

I'm still wondering what evidence suggests the problem is in these diodes.
This is a quotation from the original post: "I think there may be something
wrong with this one as the lights
occasionally go out for, as far as I can see, no apparent reason." Couldn't
this just as easily be a loose bulb, loose wire, or intermittent open
inside the generator? If it is indeed cause by the diodes, the problem
should disappear if the diodes are removed. As long as you don't ride too
fast, you shouldn't burn out the bulb. If it gets too bright, you are
riding too fast.

Thanks for all the great answers from you good people.

Maybe I can elaborate a little here.

I have used the same generator with a Lumotec light and a 4" dia.
Halogen light and had no problem. Both of these lights have a
'device' in them which is similar in appearance to what I am calling a
'zener diode'.

The light I am having trouble with is a 2 1/2" dia. Union model which
had worked perfectly for a couple of years prior to this problem.

A loose connection IS a possibility but, in all 3 of these lights, the
'device' is NOT soldered in but kind of crimped. Is it possible that
the heat from soldering it could damage it and that this is why it is
crimped?

Quoted message said:

Quoted message said:

Quoted message said:

>>

If it is indeed cause by the diodes, the problem
should disappear if the diodes are removed. As long as you don't ride too
fast, you shouldn't burn out the bulb. If it gets too bright, you are
riding too fast.

<<<<<<

I'd like to be able to ride a whatever speed the terrain determines
and NOT be concerned about the bulb burning out.

Lewis.

*********************

"Leo Lichtman" <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

I'm still wondering what evidence suggests the problem is in these diodes.
This is a quotation from the original post: "I think there may be something
wrong with this one as the lights
occasionally go out for, as far as I can see, no apparent reason." Couldn't
this just as easily be a loose bulb, loose wire, or intermittent open
inside the generator? If it is indeed cause by the diodes, the problem
should disappear if the diodes are removed. As long as you don't ride too
fast, you shouldn't burn out the bulb. If it gets too bright, you are
riding too fast.

Thanks for all the great answers from you good people.

Maybe I can elaborate a little here.

I have used the same generator with a Lumotec light and a 4" dia.
Halogen light and had no problem. Both of these lights have a
'device' in them which is similar in appearance to what I am calling a
'zener diode'.

The light I am having trouble with is a 2 1/2" dia. Union model which
had worked perfectly for a couple of years prior to this problem.

A loose connection IS a possibility but, in all 3 of these lights, the
'device' is NOT soldered in but kind of crimped. Is it possible that
the heat from soldering it could damage it and that this is why it is
crimped?

Quoted message said:

Quoted message said:

Quoted message said:

>>

If it is indeed cause by the diodes, the problem
should disappear if the diodes are removed. As long as you don't ride too
fast, you shouldn't burn out the bulb. If it gets too bright, you are
riding too fast.

<<<<<<

I'd like to be able to ride a whatever speed the terrain determines
and NOT be concerned about the bulb burning out.

Lewis.

*********************

"Leo Lichtman" <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

I'm still wondering what evidence suggests the problem is in these diodes.
This is a quotation from the original post: "I think there may be something
wrong with this one as the lights
occasionally go out for, as far as I can see, no apparent reason." Couldn't
this just as easily be a loose bulb, loose wire, or intermittent open
inside the generator? If it is indeed cause by the diodes, the problem
should disappear if the diodes are removed. As long as you don't ride too
fast, you shouldn't burn out the bulb. If it gets too bright, you are
riding too fast.

(Lewis Campbell) said:

Thanks for all the great answers from you good people.

Maybe I can elaborate a little here.

I have used the same generator with a Lumotec light and a 4" dia.
Halogen light and had no problem. Both of these lights have a
'device' in them which is similar in appearance to what I am calling a
'zener diode'.

The light I am having trouble with is a 2 1/2" dia. Union model which
had worked perfectly for a couple of years prior to this problem.

A loose connection IS a possibility but, in all 3 of these lights, the
'device' is NOT soldered in but kind of crimped. Is it possible that
the heat from soldering it could damage it and that this is why it is
crimped?

You can solder it, just try not to get it too hot. The standard thing
to do is to hold the lead close to the body with something like needle-nose
pliers while soldering.

I would imagine the device is connected across the terminals of the bulb,
so a loose connection would not cause the light to go out, but a defective
device could. Try removing it and see if the problem goes away.

www.mouser.com has the exact replacement:

http://tinyurl.com/5dumz

but you have to buy 5000 at a time.
A likely substitution would be this one:

http://tinyurl.com/6hyww

It is a little bit larger physically, but if it fits it would work.
No minimum order on that one, and it only costs 66 cents.

"Jim Smith" wrote: (clip) It is a little bit larger physically, but if it
fits it would work. (clip)
^^^^^^^^^^^^
And, if it doesn't fit, it would still work--just use longer leads and hang
it somewhere else. At the very least you will know whether the problem goes
away.

Jim Smith <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

[email hidden] (Lewis Campbell) writes:

You can solder it, just try not to get it too hot. The standard thing
to do is to hold the lead close to the body with something like needle-nose
pliers while soldering.

I would imagine the device is connected across the terminals of the bulb,
so a loose connection would not cause the light to go out, but a defective
device could. Try removing it and see if the problem goes away.

www.mouser.com has the exact replacement:

http://tinyurl.com/5dumz

but you have to buy 5000 at a time.
A likely substitution would be this one:

http://tinyurl.com/6hyww

It is a little bit larger physically, but if it fits it would work.
No minimum order on that one, and it only costs 66 cents.

******************************************

Thanks for your help.

When I go to this link:- http://tinyurl.com/5dumz I can see the
' BZ04-6V4B ' but when I go to the other link:-
http://tinyurl.com/6hyww I don't understand how this can be the same
thing.

What am I missing here?

Kind regards.

Lewis.

****************************************8

(Lewis Campbell) said:

Jim Smith <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

[email hidden] (Lewis Campbell) writes:

You can solder it, just try not to get it too hot. The standard thing
to do is to hold the lead close to the body with something like needle-nose
pliers while soldering.

I would imagine the device is connected across the terminals of the bulb,
so a loose connection would not cause the light to go out, but a defective
device could. Try removing it and see if the problem goes away.

www.mouser.com has the exact replacement:

http://tinyurl.com/5dumz

but you have to buy 5000 at a time.
A likely substitution would be this one:

http://tinyurl.com/6hyww

It is a little bit larger physically, but if it fits it would work.
No minimum order on that one, and it only costs 66 cents.

******************************************

Thanks for your help.

When I go to this link:- http://tinyurl.com/5dumz I can see the
' BZ04-6V4B ' but when I go to the other link:-
http://tinyurl.com/6hyww I don't understand how this can be the same
thing.

What am I missing here?

Hard to say. 🙂

The device, the transient voltage suppressor, is connected across the terminals
of the light bulb. Below some voltage determined by properties of the device,
it looks like a very large resistor, for larger voltages it looks like a short
circuit. So what happens is, when the voltage across the light bulb rises
to more than the set point the device starts conducting, this causes the voltage
to drop, so the device stops conducting, this couses the voltage to rise, so
the device starts to conduct. The overall effect is that, above a certain voltage,
the device looks like a resistor which automgically adjusts its resistance to keep
the voltage across it constant.

The important thing when replacing this thing is to get one that
operates at the same voltage and that can handle the load. It needs to
be bidirectional because most generators are AC. I just picked one
that looked like it was about the same voltage that they had in stock
Click on the link on the mouser page labeled "Manufacture Data Sheet,"
and even if you don't understand all of it you will see that they are
very similar devices.

Hmmm, when I looked a little closer I noticed that they changed the
way they name these things, so what used to be called a 6.4 volt is
now called a 7.5 volt. looks like the one at:

http://tinyurl.com/5rz5d

is actually a little closer to the one you have.