[EVDL List]

I've got an out-of-balance pack in the bed of a 2002 Chevy S-10. (156v total:
26 x 6v USB2000s).

That's why I'm interested in building a bunch of Zener regulators, based on
the well-known design that Lee Hart created.

There's one thing about this project that concerns me, however. The whole
point of this device is to dissipate excess energy, but more heat is not
what I want.

I take my truck to work and keep the tonneau cover locked while charging.
There are 8 "port holes" drilled in the cover, but it still gets mighty warm
in there, so the thought of all those hot bulbs doesn't really make me
smile.

But that's when I thought of an alternative: What about substituting small
fans for the bulbs? Hopefully, they could do something constructive, like
circulating the air, as opposed to just warming it up.

Would PC cooler fans work? Would there be too much power for that type of
small brushless DC motor? If you know anything about this, I'd be happy to
investigate your recommendations for specific parts.

Thanks for any guidance you might have.


Steve Kobb
http://www.myelectrictruck.com

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[EVDL List]

Steve, there are a lot of different fan motors around but the problem
continues that air moving cools only things that are sweating, like me on a
hot day. Light bulbs have the wonderful "Negative Resistance" property
because the element is made of Tungsten. High power resistors can also
withstand more power than you were expecting and are very reliable. so just
connect a fan or two to a suitable power supply and run them to power
ventilate your battery box when a thermostat says the batteries are getting
too hot and reliability will increase. The small computer fans use a solid
state circuit to eliminate brushes but they are not suitable for a variable
power source especially if it is too large!
Regards,
Dennis Miles

Steve Kobb <[email protected]> wrote:

>
> I've got an out-of-balance pack in the bed of a 2002 Chevy S-10. (156v
> total:
> 26 x 6v USB2000s).
>
> That's why I'm interested in building a bunch of Zener regulators, based on
> the well-known design that Lee Hart created.
>
> There's one thing about this project that concerns me, however. The whole
> point of this device is to dissipate excess energy, but more heat is not
> what I want.
>
> I take my truck to work and keep the tonneau cover locked while charging.
> There are 8 "port holes" drilled in the cover, but it still gets mighty
> warm
> in there, so the thought of all those hot bulbs doesn't really make me
> smile.
>
> But that's when I thought of an alternative: What about substituting small
> fans for the bulbs? Hopefully, they could do something constructive, like
> circulating the air, as opposed to just warming it up.
>
> Would PC cooler fans work? Would there be too much power for that type of
> small brushless DC motor? If you know anything about this, I'd be happy to
> investigate your recommendations for specific parts.
>
> Thanks for any guidance you might have.
>
>
> Steve Kobb
> http://www.myelectrictruck.com
>
> --
> View this message in context:
> http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3018340p3018340.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>



--
Regards,
*Dennis Lee Miles* (Director) *E.V.T.I. inc*.
*www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
EVTI-EVAEducation Chapter
*
Phone (813) ID4 - E V T I or (813) 434 - 3884 (I think word phone
numbers can be fun and good mnemonics aid memory.)
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[EVDL List]

Hello Steve,

What I did was exhaust the entire battery box with one large 100+ CFM fan
that ran on 120 vac while the charger was on. I use plumbing type 2 inch
I.D. pipe fittings design for water where they have smoother flow than the
waste type fittings. Only use PVC material where the battery fumes will
take out the standard plastic air fittings.

I drill a hole in one corner of the battery box and another at the opposite
end. The inlet use a chase elbow that pointed down and connect to a 2 inch
pvc pipe that went through the bed of the truck. A 3-M filter material is
stuff into the end of the pipe, the same filter stuff that is use swamp
coolers.

At the other end of the box, another 2 inch chase elbow is connected to the
box and is point horizontal and connected with a flexible pvc hose that is
use for water suction. This hose is connected to a inline 4 inch fan which
has 2 inch pipe stubs. The fan must be totally enclose with no expose motor
parts or wiring. From this fan, a hose is connected to a chase elbow
pointed down ward to a pipe going below the bed and than out the rear like a
exhaust pipe. Painted it black with that new plastic paint.

When I charge the EV, I have one of those flexible exhaust hoses like
service stations have which goes either under the garage door or to a port
during the winter time. You do not want to get any cross feed between the
inlet and exhaust outlets. Also no fumes should get into any of the
electrical control equipment.

I have a separate control switch for the fan that is interlock with a AC
contactor that is inline between the AC main plug and charger. The
interlock is a press/vacuum switch that detects the air flow in the exhaust
pipe. When the air flow is off, then the AC contactor will not turn on the
power to the charger. These air/flow switches are normally use to detect the
correct exhaust flow in a hot water heating system that you can get at a
heating supply co.

A commercial Ground Detector which can be adjusted and can be connected to
the AC contactor which will shut down the AC power if there is too much
conduction leakage from the battery to the EV frame.

Roland


----- Original Message -----
From: "Steve Kobb" <[email protected]>
To: <[email protected]>
Sent: Thursday, October 28, 2010 6:50 PM
Subject: [EVDL] Zener regs: Use fans instead of bulbs?


>
> I've got an out-of-balance pack in the bed of a 2002 Chevy S-10. (156v
> total:
> 26 x 6v USB2000s).
>
> That's why I'm interested in building a bunch of Zener regulators, based
> on
> the well-known design that Lee Hart created.
>
> There's one thing about this project that concerns me, however. The whole
> point of this device is to dissipate excess energy, but more heat is not
> what I want.
>
> I take my truck to work and keep the tonneau cover locked while charging.
> There are 8 "port holes" drilled in the cover, but it still gets mighty
> warm
> in there, so the thought of all those hot bulbs doesn't really make me
> smile.
>
> But that's when I thought of an alternative: What about substituting small
> fans for the bulbs? Hopefully, they could do something constructive, like
> circulating the air, as opposed to just warming it up.
>
> Would PC cooler fans work? Would there be too much power for that type of
> small brushless DC motor? If you know anything about this, I'd be happy to
> investigate your recommendations for specific parts.
>
> Thanks for any guidance you might have.
>
>
> Steve Kobb
> http://www.myelectrictruck.com
>
> --
> View this message in context:
> http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3018340p3018340.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
> | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>

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[EVDL List]

I'm hoping that Dennis meant to say that moving air cools things that are
sweating, by evaporative cooling, rather than the expression below. Moving air
cools radiators, the heat sink attached to my controller and many other things.
Moving air cools by moving the heat it has collected from one source and
spreading it elsewhere, in a manner of speaking. If air is not moving, it
reaches a temperature approaching that of the heat source, which is likely to
overheat. One concept that inspires extended discussion is wind chill, which
does apply only to wet objects, but one cannot reject convection cooling. I can
barely recall my high school classes, but it's conduction, convection and a
couple of others.

One can pick up some fans on eBay that have substantial energy requirements. I
purchased an inexpensive 12" radiator fan that uses 12v and pulls seven to ten
amps on startup and runs at about five amperes overall. It's noisy as an ICE
engine, though and would certainly ventilate a battery box.



------------------------------

Original Message: 11
Date: Thu, 28 Oct 2010 23:31:47 -0400
From: Dennis Miles <[email protected]>
Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?

Steve, there are a lot of different fan motors around but the problem
continues that air moving cools only things that are sweating, like me on a
hot day. Light bulbs have the wonderful "Negative Resistance" property
because the element is made of Tungsten. High power resistors can also
withstand more power than you were expecting and are very reliable. so just
connect a fan or two to a suitable power supply and run them to power
ventilate your battery box when a thermostat says the batteries are getting
too hot and reliability will increase. The small computer fans use a solid
state circuit to eliminate brushes but they are not suitable for a variable
power source especially if it is too large!
Regards,
Dennis Miles

End of Original Message: 11
------------------------------




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[EVDL List]

I think fans would be a poor choice in this application.

Unless the fan is blowing air in/out of the box, all it's doing is
stirring the same hot air around inside the box. This won't cool
anything. All the energy fed to the fan is still converted into heat
inside the box.

Adding ductwork so the fans actually do move air in/out of the box would
be a big project.

The cheap little computer fans are brushless DC, which means they have
an IC chip to run them. Like most chips, they have a narrow range of
acceptable operating voltages. Too low or too high, and they fail. Also,
they aren't really built to survive in such a harsh environment. They
are going to get hot, cold, wet, shook around from road vibration, etc.

If you want to get the heat out of the battery box, put the regs outside
the box. Or, add an independent cooling system to extract heat from the
box. A fan, or maybe a liquid cooling loop.
--
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
leeahart earthlink.net | That's how the light gets in -- Leonard Cohen

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[EVDL List]

PS: One more thing occurred to me. I have a set of 24 of these
Zener-Lamp regulators built for 12v batteries if anyone is interested.
Price is $10 each plus shipping.

--
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
leeahart earthlink.net | That's how the light gets in -- Leonard Cohen

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[EVDL List]

Hi, Fred,
Thanks for not calling me ignorant, I was merely trying to suggest
ventilation with cooler outside air is better than stirring the air inside
the box. A tungsten filament lamp bulb makes a better loosely defined load
that may vary. and ventilating the box is more important than stirring up
the air in the box. Use that convection. The methods are [I think],
Cunduction, Convection, and Radiation, but Evaporation and melting [I
forget the word for that.] freezing and condensing are changes in "State"
which absorb or release a large amount of heat energy in the change. (And I
haven't had a college physics class since 1965.)

Regards,
*Dennis Lee Miles*
============================================================

fred <[email protected]> wrote:

> I'm hoping that Dennis meant to say that moving air cools things that are
> sweating, by evaporative cooling, rather than the expression below. Moving
> air
> cools radiators, the heat sink attached to my controller and many other
> things.
> Moving air cools by moving the heat it has collected from one source and
> spreading it elsewhere, in a manner of speaking. If air is not moving, it
> reaches a temperature approaching that of the heat source, which is likely
> to
> overheat. One concept that inspires extended discussion is wind chill,
> which
> does apply only to wet objects, but one cannot reject convection cooling. I
> can
> barely recall my high school classes, but it's conduction, convection and a
> couple of others.
>
> One can pick up some fans on eBay that have substantial energy
> requirements. I
> purchased an inexpensive 12" radiator fan that uses 12v and pulls seven to
> ten
> amps on startup and runs at about five amperes overall. It's noisy as an
> ICE
> engine, though and would certainly ventilate a battery box.
>
>
>
> ------------------------------
>
> Original Message: 11
> Date: Thu, 28 Oct 2010 23:31:47 -0400
> From: Dennis Miles <[email protected]>
> Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?
>
> Steve, there are a lot of different fan motors around but the problem
> continues that air moving cools only things that are sweating, like me on a
> hot day. Light bulbs have the wonderful "Negative Resistance" property
> because the element is made of Tungsten. High power resistors can also
> withstand more power than you were expecting and are very reliable. so just
> connect a fan or two to a suitable power supply and run them to power
> ventilate your battery box when a thermostat says the batteries are getting
> too hot and reliability will increase. The small computer fans use a solid
> state circuit to eliminate brushes but they are not suitable for a variable
> power source especially if it is too large!
> Regards,
> Dennis Miles
>
> End of Original Message: 11
> ------------------------------
>
>
>
>
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--
Regards,
*Dennis Lee Miles* (Director) *E.V.T.I. inc*.
*www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
EVTI-EVAEducation Chapter
*
Phone (813) ID4 - E V T I or (813) 434 - 3884 (I think word phone
numbers can be fun and good mnemonics aid memory.)
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[EVDL List]

I just did some Lee Hart regs and got to see them working . The
light bulb does not have a lot of voltage drop across it as most of
the voltage is dropped across the zenor diodes and they do get hot,
the light bulbs see about 1 to 2 volts at 1/2 an amp so you would need
a fan that would run on 1 or 2 volts . The bulbs don't get that hot .
Before I tried Lees set up I fooled around with some transistors and
used a Zenor diode to switch them on. Never got this working well
enough to use . I also tried a 3v relay with a11v zenor and let the
relay control the load. The problem I kept coming back to was getting
25 to work some what at the same voltage and keep working , The guy
I'm working for loves them light bulb reg ,, and I've put them on all
his nev's .

Here is a picture of the box I did on his Porsche. The first time we
charged it with the new batteries.. you could really see the
differences in the battery voltages. One light would come on and then
another..and another. They didn't all come on at the same time, or
even close. After it was done charging, I turned the charger back ON
and they all did come on the second time, dimly.

http://greenshedconversions.com/Projects.aspx

Because the second set, I had the batteries in a box that could not be
accessed. I took a block of 1/2" aluminum, cut it in half, milled
the two halves to fit flush, ( I am working in a shop that has all
kinds of neat tools)... then drilled holes, a hair smaller than the
size of the diodes. Right along the line of the two pieces of
aluminum. Unbolted the two pieces and placed the diodes inside, to
sandwich the diodes in this block of aluminum.

I also milled along the face so that the bed where the diodes sat was
no wider than the actual diode. This big chunk of aluminum which was
about 6" long for 10 batteries was then bolted to the aluminum battery
box. Even with this much aluminum, the thing still gets pretty hot.
but as I can keep my hand on it... I am hoping it will dissipate
enough heat. My customer wanted all the light bulbs in one box and
this is a bit of a wiring challenge. I didn't use any fuses, as the
diodes themselves, from experience.... seem to work very well as
fuses. ( I would suggest getting at least 10 more diodes and 10 more
light bulbs than you need). I encourage anyone who does Lee's set up
to make him a donation ( check is in the mail Lee.. I am going to be
the change I want to see).

Steve Clunn

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[EVDL List]

am very interested in the zener regs, could I see pic ? how do they work? I
will be using two banks of 9- 12volt gel batteries and I think I would like
to monitor and charge each battery individually, what do you think? am new
to this

Lee Hart <[email protected]> wrote:

> PS: One more thing occurred to me. I have a set of 24 of these
> Zener-Lamp regulators built for 12v batteries if anyone is interested.
> Price is $10 each plus shipping.
>
> --
> Lee A. Hart | Ring the bells that still can ring
> 814 8th Ave N | Forget the perfect offering
> Sartell MN 56377 | There is a crack in everything
> leeahart earthlink.net | That's how the light gets in -- Leonard Cohen
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
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>
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[EVDL List]

On 30 Oct 2010 at 21:06, Dan Payne wrote:

> am very interested in the zener regs, could I see pic? how do they work?

http://www.evdl.org/pages/hartregs.html

http://www.evdl.org/docs/zenerregs.pdf

David Roden - Akron, Ohio, USA
EVDL Administrator

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[EVDL List]

I've been trying to design heat sinks to mount the diodes away from the
battaries. Long story short, I'll be using the batteries as heat sinks.

The light bulbs have a non-linear voltage-current curve. Once the current
gets to a certain point the resistance increases. Would a fan motor have a
similar behavior? Heat sinks can be smaller if there's a fan right there.

Jack
--
View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3020784p3030932.html
Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com.

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[EVDL List]

It is very important how you install any type of fans around a battery box.
Do not pressurize the box by inputting the air from the out side. It is
better to exhaust the air with a totally enclose arc proof fan.

Make sure there is no cross air path between the input air and exhaust air.
I install a hose off the exhaust pipe to the outside of the building while I
take warm 80 F. air from the inside.

Mounting a standard fan inside a battery box, is very dangerous, because if
there is any expose fan motor parts, it may blow up your battery box.

If your batteries are a flooded type, a fan inputting air or running in a
enclose battery container, will blow out all the fumes through any seals and
may get into any devices or compartments that produces a arc.

My first EV had a battery box blower fans which not only exhaust down and
out like a exhaust system, but also blew the fumes into other compartments.
When I turn off the battery charger charger circuit breaker it produce a
spark which blew the covers off my battery box which sent them up through
the hatch back glass and about 30 feet in the air.

Roland


----- Original Message -----
From: "rocketeer" <[email protected]>
To: <[email protected]>
Sent: Sunday, November 07, 2010 8:11 AM
Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?


>
> I've been trying to design heat sinks to mount the diodes away from the
> battaries. Long story short, I'll be using the batteries as heat sinks.
>
> The light bulbs have a non-linear voltage-current curve. Once the current
> gets to a certain point the resistance increases. Would a fan motor have
> a
> similar behavior? Heat sinks can be smaller if there's a fan right there.
>
> Jack
> --
> View this message in context:
> http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3020784p3030932.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
> _______________________________________________
> | REPLYING: address your message to [email protected] only.
> | Multiple-address or CCed messages may be rejected.
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>

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[EVDL List]

rocketeer wrote:
> I've been trying to design heat sinks to mount the diodes away from
> the batteries. Long story short, I'll be using the batteries as heat
> sinks.

I spent a lot of time on it, and came to the same conclusion. The
cheap easy-to-get diodes are in axial-lead plastic cases. But they
aren't easy to heatsink. I wound up putting them in the ring terminals
with thermally conductive epoxy.

You could use a metal-cased zeners, like the 1N3998/1N3999 (6.2v and
6.8v 10w stud mount). Or, use a small zener and a power transistor
(1N5232/1N5234 and a TIP31). These are easier to heatsink; but they cost
more, don't work as well, and are harder to build.

> The light bulbs have a non-linear voltage-current curve. Once the
> current gets to a certain point the resistance increases. Would a
> fan motor have a similar behavior? Heat sinks can be smaller if
> there's a fan right there.

It might; it depends on the type of motor. But the voltage it needs will
be a lot higher than the 2.5v light bulb. Good luck finding a fan with a
2.5v motor.

--
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
leeahart earthlink.net | That's how the light gets in -- Leonard Cohen

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[EVDL List]

Yeah the tolerance on the 10W zeners is aweful.

Jack
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[EVDL List]

I haven't been ably to find an epoxee that proclaims to be thermally
conductive. What do you use?

Jack

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[EVDL List]

Say, while this thread is active and I've got your attention, what do you
think of using 5.6V and 8.2V zener diodes and two bulbs in parallel?

Thanks for your time on this.

Jack

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[EVDL List]

I was thinking of a higher voltage turn on and a quicker rise in current.
Redundancy doesn't suck either..

Jack

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[EVDL List]

Wowee Roland you could make some money in Hollywood with a plot like that! Bad
guy sneaks a substandard fan into the battery box of the good guy's car...


Thanks for the safety warning! Do lithiums ever emit explosive (or corrosive)
gas, or is that just a Lead Acid thing?




________________________________
From: Roland Wiench <[email protected]>
To: Electric Vehicle Discussion List <[email protected]>
Sent: Sun, November 7, 2010 10:47:38 AM
Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?

It is very important how you install any type of fans around a battery box.
Do not pressurize the box by inputting the air from the out side. It is
better to exhaust the air with a totally enclose arc proof fan.

Make sure there is no cross air path between the input air and exhaust air.
I install a hose off the exhaust pipe to the outside of the building while I
take warm 80 F. air from the inside.

Mounting a standard fan inside a battery box, is very dangerous, because if
there is any expose fan motor parts, it may blow up your battery box.

If your batteries are a flooded type, a fan inputting air or running in a
enclose battery container, will blow out all the fumes through any seals and
may get into any devices or compartments that produces a arc.

My first EV had a battery box blower fans which not only exhaust down and
out like a exhaust system, but also blew the fumes into other compartments.
When I turn off the battery charger charger circuit breaker it produce a
spark which blew the covers off my battery box which sent them up through
the hatch back glass and about 30 feet in the air.



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[EVDL List]

I use Mouser 590-832-TC-450ML Epoxy Compound that is design for electrical
and electronics potting.

There is a good site call Projects by Mark Brueggemm that shows photo
details of assembling varies, zeners ratings, matching and testing the
zeners and different voltage for different batteries using Lees BMS shunts
with a total list of components and sources.

I use two 6.8 V - 5 watt zeners and two lamps in parallel for my 6 volt
flood batteries.

I install the units in a abs chassis box that is design for a lens cover for
switch boards from www.surplussales.com. I also got from them the lamp
holders and screw on lens. If a bulb burns out, all I have to do is unscrew
the lens and change the bulb.

If they have no more lamp holders for the lamps, then you can mount the
lamps to the chassis board and drill and tap the box using a fine thread 1/2
inch bolt for screwing on the lens.

The chassis box has it cover on the bottom which I recess about 1/16 of a
inch and trawl a layer of black RTV to seal the cover. I made the cover,
and a chassis board from a sheet of black PVC to set the components on. To
replace any of the components, just cut the RTV at the edge of the cover to
remove it.

Use two grommets for the two cables that go into the box. Using a parallel
circuit, I use a two wire cable in a chemical and oil resistance cable that
goes to the terminal lugs.

See at: http://www.teva2.com/projects.htm

or just type Projects Lees Shunts.
Roland


----- Original Message -----
From: "rocketeer" <[email protected]>
To: <[email protected]>
Sent: Monday, November 08, 2010 9:07 AM
Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?


>
> I haven't been ably to find an epoxee that proclaims to be thermally
> conductive. What do you use?
>
> Jack
>
> --
> View this message in context:
> http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3020784p3032318.html
> Sent from the Electric Vehicle Discussion List mailing list archive at
> Nabble.com.
>
> _______________________________________________
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[EVDL List]

Loctite 383, repairable
http://www.ellsworth.com/display/productdetail.html?productid=2081
Loctite 384 permanent
http://www.ellsworth.com/display/productdetail.html?productid=2327


----- Original Message ----
From: rocketeer <[email protected]>
To: [email protected]
Sent: Mon, November 8, 2010 12:07:45 PM
Subject: Re: [EVDL] Zener regs: Use fans instead of bulbs?


I haven't been ably to find an epoxee that proclaims to be thermally
conductive. What do you use?

Jack

--
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http://electric-vehicle-discussion-list.413529.n4.nabble.com/Zener-regs-Use-fans-instead-of-bulbs-tp3020784p3032318.html

Sent from the Electric Vehicle Discussion List mailing list archive at
Nabble.com.

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