Post by thread:[EE] Automotive Temperature Range

'[EE] Automotive Temperature Range'

I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?  

Now, just have to get to work on that environmental chamber…..

-- Lawrence Lile, P.E.

Electrical and Electronic Solutions

Project Solutions Companies

HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

---

Outgoing mail is certified Virus Free.

Checked by AVG anti-virus system (http://www.grisoft.com).

Version: 6.0.762 / Virus Database: 510 - Release Date: 9/13/2004

 _______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

At the extreme- header paint is rater for +1200F

so I think it matters "where"

D

At 09:31 AM 10/8/04, you wrote:

{Quote hidden}>I know that microprocessors are rated in industrial or automotive 

>temperature ranges. Automotive, according to MCHIP is -40C to 

>85C.   However, I have reason to suspect that the ranges of temperatures 

>seen under the hood of a car might be different.  If one were testing an 

>electronic circuit to go under the hood, what temperature ranges would be 

>recommended?

>

>Now, just have to get to work on that environmental chamber…..

>-- Lawrence Lile, P.E.

>Electrical and Electronic Solutions

>Project Solutions Companies

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Military operating temp range is speced from -55c to +150c

Industrial operating temp range is sepced from -40 to +125c.

Automotive operating temp range -25c to +85c

Commercial operating temp range 0c to +70c

Storage temp range is -65c to +150c

NOTE: these are not ambient temp ranges, but rather limits of the hottest or coldest silicon junction.

If a power handling device is being pushed hard it could function below the min. but would fail before the max.

You will notice underhood electronics are strategically located to get air flow and stay well clear of the exhaust system.

Personally I prefer underdash rather than underhood, not many people drive around with the inside car temp below -40c or above 125c          ;-)

KF4HAZ - Lonnie

----- From: "Lawrence Lile" <llile@

I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?  

Now, just have to get to work on that environmental chamber….. 

-- Lawrence Lile, P.E.

Electrical and Electronic Solutions

Project Solutions Companies

HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Thanks.  These ranges are according to whom?  The numbers vary depending on where I look.

-- Lawrence Lile, P.E.

Electrical and Electronic Solutions

Project Solutions Companies

http://www.projsolco.com

573-443-7100 ext 221

> {Original Message removed}
Ok, no bolting onto exhaust manifolds or engines then.  Let's say bolted onto the firewall, far from exhaust pipes.

If the temperature range for the PIC is up to 85C, would you actually *test* a circuit at that temperature?   

-- Lawrence Lile, P.E.

Electrical and Electronic Solutions

Project Solutions Companies

http://www.projsolco.com

> {Original Message removed}
Those are the "general" definitions from Motorola and Fairchild databooks,

 some components (such as pass transistors & finals) use different ratings, some as high as +175c operating junction temp.

KF4HAZ - Lonnie

----- From: "Lawrence Lile" <llile@

> Thanks.  These ranges are according to whom?  The numbers vary depending on where I look.

> 

> 

> 

> -- Lawrence Lile, P.E.

> Electrical and Electronic Solutions

> Project Solutions Companies

> http://www.projsolco.com

> 573-443-7100 ext 221

> 

> > {Original Message removed}
85C is very accurate. Engine cooling systems are set normally at 180F max (cold temp operation) and 165F max (hot temp operation). As we all know, there is a differential in the engine compartment, especially in warm weather. 85C is as hot as it gets for a properly maintained engine.

Many of my designs are automotive. The problems, if any, are always toward the high end temp; engine compartments rarely stay at -40C for more than a minute. PICs

work well at high temperatures as long as the clock speed is lowered; as temperatures increase, the gain of the oscillator falls to a point at which it may not oscillate (due

to higher leakage across silicon with increased temperature. This is also true of OPAMPS and other analog devices as well. You MIGHT need to rig a test chamber for selecting analog components if 85C is what you MUST meet.

Capacitors will be your main problem; aluminum electrolytics dry out very rapidly above 50C unless they are encapsulated with a high-temperature plastic (which then negates their "safety valve"), so you will need to use solid tantalum or ceramics. Lately nothing of mine is being mounted in the engine compartment, so I might be slightly out of touch. The next most important item is wiring; wiring should be 105C minimally, but Teflon is the best insulator.

The most reliable high temperature work is being done by oil field "downhole" instrument makers, who have to contend with 100C constantly.

Hope this helps.

--Bob

Lawrence Lile wrote:

{Quote hidden}>I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?  

>

> 

>

> 

>

>Now, just have to get to work on that environmental chamber…..

>

> 

>

>-- Lawrence Lile, P.E.

>

>Electrical and Electronic Solutions

>

>Project Solutions Companies

>

>HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

>

> 

>

>

>---

>Outgoing mail is certified Virus Free.

>Checked by AVG anti-virus system (http://www.grisoft.com).

>Version: 6.0.762 / Virus Database: 510 - Release Date: 9/13/2004

> 

>_______________________________________________

>http://www.piclist.com

>View/change your membership options at

>http://mailman.mit.edu/mailman/listinfo/piclist

>

>  

>

-- Note: Attachments must be sent to

 spam_OUTattachTakeThisOuTengineer.cotse.net, and  MAY delay replies to this message.

        520-219-2363

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Actually the firewall is not as good a location as say behind the headlight bucket.

And no if the max is speced @ +85c that would be too high for ambient if there was any heat being generated by the device.

In this case max ambient=85c-(Pd*Rth junction to ambient), or if using a heatsink

Max Ambient=MaxTempSpec-(Pd*(Rth junction to case+Rth case to sink+Rth sink to ambient))

Pd is Power dissipated, Rth is Thermal Resistance

KF4HAZ - Lonnie

----- From: "Lawrence Lile" <llile@

> Ok, no bolting onto exhaust manifolds or engines then.  Let's say bolted onto the firewall, far from exhaust pipes.

> 

> If the temperature range for the PIC is up to 85C, would you actually *test* a circuit at that temperature?   

> 

> -- Lawrence Lile, P.E.

> Electrical and Electronic Solutions

> Project Solutions Companies

> http://www.projsolco.com

> 

> > {Original Message removed}
Underhood temperatures can and usually break the 85C mark on most

automobiles.

The current trend in the market is to make the engines leaner so rarely

do you find a 180F thermostat in your car. More along the lines of 195F.

Your highest temperatures will be not while driving but after you park your

car on a hot summer day. The engine bay gets heat soaked and it is not

uncommon

to see temperatures as high as 250F!

Your best bet is the cab inside the car after baking in the sun all day you

shouldn't cross 150F.

Cheers,

M.

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

piclist-bounces@mit.edu wrote:

> If the temperature range for the PIC is up to 85C, would you actually

> *test* a circuit at that temperature? 

depends of course on the test and reasons for the test. I do test 

circuits that high, and higher (until it quits working, actually).

checking my notes, I had a PIC-based design that was tested from

-20C to 90C in our lab, under power, functioning properly, within

the required accuracy. Our  test chamber maxed out at 100C, and 

the system accuracy as a whole fell outside requirements around

95C. By accuracy, I mean analog measurements made with an INA.

if you mount this circuit inside the engine bay, then some areas

will exceed 85C, but other areas won't, as already mentioned. 

Properly located, where the vehicle mfg located other electronics,

I'd say 85C is a good 'max' temp target to shoot for.

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

piclist-bounces@mit.edu wrote:

> 85C is very accurate. Engine cooling systems are set normally at 180F

> max (cold temp operation) and 165F max (hot temp operation). As we all

> know, there is a differential in the engine compartment, especially in

> warm weather. 85C is as hot as it gets for a properly maintained

> engine. 

> 

here's someone who actually measured the temperature, but bear in

mind where he located the sensor

http://www.teirney.net/civic/TemperatureReadings.htm

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

----- From: "Bob Axtell" <engineer@

> <snip> As we all  know, there is a differential in the engine compartment, </snip>

For front wheel drive yes, but my trucks differential is way back between the rear tires ;-)

Man Fridays can get real boring around here when you don't have something new to do.

KF4HAZ - Lonnie

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

At 02:57 PM 10/8/2004, Falcon Wireless Tech Support - KF4HAZ wrote:

>----- From: "Bob Axtell" <engineer@

>

>> <snip> As we all  know, there is a differential in the engine compartment, </snip>

>

>For front wheel drive yes, but my trucks differential is way back between the rear tires ;-)

>

>Man Fridays can get real boring around here when you don't have something new to do.

Mine's got one in each place!  

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Certainly! My wife and I had a massage today, so my fingers are

too limp to type...

My point was that because the fan moves hot air in large volume,

people tend to think that the underhood temperatures are much higher than

they actually are. But even here in Tucson, 85C seems to be the max unless

there is an engine defect or a sudden loss of coolant.

BTW... where is KF4? Florida?

--Bob

Falcon Wireless Tech Support - KF4HAZ wrote:

{Quote hidden}>----- From: "Bob Axtell" <engineer@

>

>  

>

>><snip> As we all  know, there is a differential in the engine compartment, </snip>

>>    

>>

>

>For front wheel drive yes, but my trucks differential is way back between the rear tires ;-)

>

>Man Fridays can get real boring around here when you don't have something new to do.

>

>KF4HAZ - Lonnie

>

>

>_______________________________________________

>http://www.piclist.com

>View/change your membership options at

>http://mailman.mit.edu/mailman/listinfo/piclist

>

>  

>

-- 

Note: Attachments must be sent to

 .....attachKILLspam@spam@engineer.cotse.net, and 

 MAY delay replies to this message.

        520-219-2363

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

> Properly located, where the vehicle mfg located other electronics,

> I'd say 85C is a good 'max' temp target to shoot for.

I think this is probably a safe bet, because I'm sure the manufacturers

make sure there /is/ a location with temperatures that allow them to use

85C spec'ed parts.

Gerhard

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Gerhard Fiedler wrote:

>>Properly located, where the vehicle mfg located other electronics,

>>I'd say 85C is a good 'max' temp target to shoot for.

> 

> 

> I think this is probably a safe bet, because I'm sure the manufacturers

> make sure there /is/ a location with temperatures that allow them to use

> 85C spec'ed parts.

Typically under the drivers seat since it is out of sun,

and will get warmed up once the driver gets in.

Ford and GM seem to like putting their engine controllers

there, rather than under the hood on the side wall, like

Chrysler.

R

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

>>>Properly located, where the vehicle mfg located other electronics,

>>>I'd say 85C is a good 'max' temp target to shoot for.

>> 

>> I think this is probably a safe bet, because I'm sure the manufacturers

>> make sure there /is/ a location with temperatures that allow them to use

>> 85C spec'ed parts.

> 

> Typically under the drivers seat since it is out of sun, and will get

> warmed up once the driver gets in. Ford and GM seem to like putting

> their engine controllers there, rather than under the hood on the side

> wall, like Chrysler.

IIRC, at least some GMs have their powertrain control module in a spot

right behind the right front wheel. Under the driver's seat is probably a

much friendlier climate :)

Gerhard

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

>Military operating temp range is speced from -55c to +150c

>Industrial operating temp range is sepced from -40 to +125c.

never come across military devices rated to 150C, always been 125C that I am

aware. maybe there have been special devices rated to 150C.

Industrial has generally been to 0C +80C that I have come across,

effectively a commercial temp with extended top range.

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

>-----Original Message-----

>From: piclist-bouncesKILLspammit.edu [.....piclist-bouncesKILLspam.....mit.edu] 

>On Behalf Of Alan B. Pearce

>Sent: 11 October 2004 09:47

>To: Microcontroller discussion list - Public.

>Subject: Re: [EE] Automotive Temperature Range

>

>

>>Military operating temp range is speced from -55c to +150c Industrial 

>>operating temp range is sepced from -40 to +125c.

>

>never come across military devices rated to 150C, always been 

>125C that I am aware. maybe there have been special devices 

>rated to 150C.

>

>Industrial has generally been to 0C +80C that I have come 

>across, effectively a commercial temp with extended top range.

Industrial is normaly -40 to +85 isn't it? 

Regards

Mike

=======================================================================

This e-mail is intended for the person it is addressed to only. The

information contained in it may be confidential and/or protected by

law. If you are not the intended recipient of this message, you must

not make any use of this information, or copy or show it to any

person. Please contact us immediately to tell us that you have

received this e-mail, and return the original to us. Any use,

forwarding, printing or copying of this message is strictly prohibited.

No part of this message can be considered a request for goods or

services.

=======================================================================

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

KF4HAZ  Alabama EM63um N 33º  37'  07.0"    W 86º  14'  39.7"  (@ tower base) to be specific.

But the thing you are overlooking is a phenomenon known in the automotive industry as a "hot soak"

This occurs after the engine is shut off and is no longer getting air flow.

Even though the coolant temp is say 95c during this period, the cylinders & exhaust system including the catalytic converter are a great deal hotter, this can cause the underhood temp to rise drastically.

Many of the Auto makers had trouble with their early attempts to put electronics under the hood.

This resulted in numerous recalls, once they figured out why the car wouldn't run after being turned off for 20 or 30 minutes but after a few hours everything was fine.

I have BTDT and learned from it, underdash is preferable to underhood.

KF4HAZ - Lonnie

----- From: "Bob Axtell" <engineer@

{Quote hidden}> Certainly! My wife and I had a massage today, so my fingers are

> too limp to type...

> 

> My point was that because the fan moves hot air in large volume,

> people tend to think that the underhood temperatures are much higher than

> they actually are. But even here in Tucson, 85C seems to be the max unless

> there is an engine defect or a sudden loss of coolant.

> 

> BTW... where is KF4? Florida?

> 

> --Bob

> 

> Falcon Wireless Tech Support - KF4HAZ wrote:

> 

> >----- From: "Bob Axtell" <engineer@

> >

> >  

> >

> >><snip> As we all  know, there is a differential in the engine compartment, </snip>

> >>    

> >>

> >

> >For front wheel drive yes, but my trucks differential is way back between the rear tires ;-)

> >

> >Man Fridays can get real boring around here when you don't have something new to do.

> >

> >KF4HAZ - Lonnie

> >

> >

> >_______________________________________________

> >http://www.piclist.com

> >View/change your membership options at

> >mailman.mit.edu/mailman/listinfo/piclist

> >

> >  

> >

> 

> 

> -- 

> Note: Attachments must be sent to

>  EraseMEattachspam_OUTTakeThisOuTengineer.cotse.net, and 

>  MAY delay replies to this message.

>         520-219-2363

> 

> _______________________________________________

> http://www.piclist.com

> View/change your membership options at

> mailman.mit.edu/mailman/listinfo/piclist

> 

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Way back when (1980), I worked on the keyless entry module for Ford.  

Ford's specs at that time required an operating temperature range of 

-40C to +85C.  These modules were located behind the glove box or in the 

trunk at that time.

Gerhard Fiedler wrote:

{Quote hidden}>>Properly located, where the vehicle mfg located other electronics,

>>I'd say 85C is a good 'max' temp target to shoot for.

>>    

>>

>

>I think this is probably a safe bet, because I'm sure the manufacturers

>make sure there /is/ a location with temperatures that allow them to use

>85C spec'ed parts.

>

>Gerhard

>_______________________________________________

>http://www.piclist.com

>View/change your membership options at

>http://mailman.mit.edu/mailman/listinfo/piclist

>

>  

>

-- 

Thanks,

Scott Thomas

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Hi Lawrence.

>From what I remember ...

Commercial : 0*C to +70*C

Industrial : -40*C to +85*C

Automotive : -40*C to +125*C

Military   : -55*C to +150*C

WBR Dmitry.

Lawrence Lile wrote:

{Quote hidden}> 

> I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?

> 

> 

> 

> 

> 

> Now, just have to get to work on that environmental chamber…..

> 

> 

> 

> -- Lawrence Lile, P.E.

> 

> Electrical and Electronic Solutions

> 

> Project Solutions Companies

> 

> HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

> 

> 

> 

> ---

> Outgoing mail is certified Virus Free.

> Checked by AVG anti-virus system (http://www.grisoft.com).

> Version: 6.0.762 / Virus Database: 510 - Release Date: 9/13/2004

> 

> _______________________________________________

> http://www.piclist.com

> View/change your membership options at

> mailman.mit.edu/mailman/listinfo/piclist

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Bob Axtell wrote:

> The most reliable high temperature work is being done by oil field

> "downhole" instrument makers, who have to contend with 100C

> constantly.

If only it were that cold, my life would be a lot easier :-)

All of our downhole equipment is rated to spend its life at 150C or 175C,

some up to 200C, and we're looking at even higher temperatures for one

application.  And these aren't survey tools which only have to survive a

few hours- they go on the end of pumps and are expected to last a few

years.

Typical temperatures are 120-150C at the bottom of a downhole oil pump, so

it really needs to work at that temperature, it's not just a number for the

spec sheet!

As you can probably imagine, there are a _lot_ of issues to deal with!

Nigel

--

Nigel Orr, Design Engineer                 nigelspam_OUTaxoninstruments.co.uk

Axon Instruments Ltd., Wardes Road,Inverurie,Aberdeenshire,UK,AB51 3TT

               Tel:+44 1467 622332 Fax:+44 1467 625235

                   http://www.axoninstruments.co.uk

This e-mail and any files transmitted with it ("E-mail") is intended

solely for the addressee(s) and may contain confidential and/or legally

privileged information.  If you are not the addressee(s), any

disclosure, reproduction, copying, distribution or other use of the

E-mail is prohibited.  If you have received this E-mail in error,

please delete it and notify the sender immediately via our switchboard

or return e-mail.

Neither the company nor any individual sending this E-mail accepts any

liability in respect of the content (including errors and omissions)

and timeliness of the E-mail which arise as a result of transmission.

If verification is required, please request a hard copy version

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

>From Motorola's & Fairchild's data books...

Commercial: 0c to +70c

Automotive: -25c to + 85c

Industrial: -40 to +125c

Military -55c to +150c

----- From: <vze27bym@

{Quote hidden}> Hi Lawrence. 

> >From what I remember ...

> 

> Commercial : 0*C to +70*C

> Industrial : -40*C to +85*C

> Automotive : -40*C to +125*C

> Military   : -55*C to +150*C

> 

> WBR Dmitry.

> 

> 

> 

> Lawrence Lile wrote:

> > 

> > I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?

> > 

> > 

> > 

> > 

> > 

> > Now, just have to get to work on that environmental chamber…..

> > 

> > 

> > 

> > -- Lawrence Lile, P.E.

> > 

> > Electrical and Electronic Solutions

> > 

> > Project Solutions Companies

> > 

> > HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Out of curiosity.

Google has showed several different opinions as well.

The key answer might be extended industrial and extended

automotive for the -40 +125 range ?

WBR Dmitry.

Falcon Wireless Tech Support - KF4HAZ wrote:

{Quote hidden}> 

> >From Motorola's & Fairchild's data books...

> 

> Commercial: 0c to +70c

> Automotive: -25c to + 85c

> Industrial: -40 to +125c

> Military -55c to +150c

> 

> ----- From: <vze27bym@

> > Hi Lawrence.

> > >From what I remember ...

> >

> > Commercial : 0*C to +70*C

> > Industrial : -40*C to +85*C

> > Automotive : -40*C to +125*C

> > Military   : -55*C to +150*C

> >

> > WBR Dmitry.

> >

> >

> >

> > Lawrence Lile wrote:

> > >

> > > I know that microprocessors are rated in industrial or automotive temperature ranges. Automotive, according to MCHIP is -40C to 85C.   However, I have reason to suspect that the ranges of temperatures seen under the hood of a car might be different.  If one were testing an electronic circuit to go under the hood, what temperature ranges would be recommended?

> > >

> > >

> > >

> > >

> > >

> > > Now, just have to get to work on that environmental chamber…..

> > >

> > >

> > >

> > > -- Lawrence Lile, P.E.

> > >

> > > Electrical and Electronic Solutions

> > >

> > > Project Solutions Companies

> > >

> > > HYPERLINK "http://www.projsolco.com"http://www.projsolco.com

> 

> _______________________________________________

> http://www.piclist.com

> View/change your membership options at

> mailman.mit.edu/mailman/listinfo/piclist

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist

Thanks for the heads up Nigel. I have been away from downhole tools a long

time, as you can tell.

--Bob

Nigel Orr wrote:

{Quote hidden}>Bob Axtell wrote:

>  

>

>>The most reliable high temperature work is being done by oil field

>>"downhole" instrument makers, who have to contend with 100C

>>constantly.

>>    

>>

>

>If only it were that cold, my life would be a lot easier :-)

>

>All of our downhole equipment is rated to spend its life at 150C or 175C,

>some up to 200C, and we're looking at even higher temperatures for one

>application.  And these aren't survey tools which only have to survive a

>few hours- they go on the end of pumps and are expected to last a few

>years.

>

>Typical temperatures are 120-150C at the bottom of a downhole oil pump, so

>it really needs to work at that temperature, it's not just a number for the

>spec sheet!

>

>As you can probably imagine, there are a _lot_ of issues to deal with!

>

>Nigel

>--

>Nigel Orr, Design Engineer                 @spam@nigelKILLspamaxoninstruments.co.uk

>Axon Instruments Ltd., Wardes Road,Inverurie,Aberdeenshire,UK,AB51 3TT

>               Tel:+44 1467 622332 Fax:+44 1467 625235

>                   http://www.axoninstruments.co.uk

>

>This e-mail and any files transmitted with it ("E-mail") is intended

>solely for the addressee(s) and may contain confidential and/or legally

>privileged information.  If you are not the addressee(s), any

>disclosure, reproduction, copying, distribution or other use of the

>E-mail is prohibited.  If you have received this E-mail in error,

>please delete it and notify the sender immediately via our switchboard

>or return e-mail.

>

>Neither the company nor any individual sending this E-mail accepts any

>liability in respect of the content (including errors and omissions)

>and timeliness of the E-mail which arise as a result of transmission.

>If verification is required, please request a hard copy version

>

>

>_______________________________________________

>http://www.piclist.com

>View/change your membership options at

>http://mailman.mit.edu/mailman/listinfo/piclist

>

>  

>

-- 

Note: Attachments must be sent to

 KILLspamattachKILLspamengineer.cotse.net, and 

 MAY delay replies to this message.

        520-219-2363

_______________________________________________

http://www.piclist.com

View/change your membership options at

http://mailman.mit.edu/mailman/listinfo/piclist