Engine Compartment Ambient Temperature Range?
Tim Wescott
What is a safe figure to assume for engine compartment ambient
temperatures? Semiconductor companies seem to agree that the automotive
temperature range is -40C to +85C, but that's at the part, and you need
some temperature drop to the outside world for heat to flow.
I'm sure the answer is some variation of "that depends on what part of
the engine compartment", so to qualify, I'm thinking of places where one
may reasonably mount electronics, like inner fenders or the firewall.
If there were a chart somewhere that listed spots and expected high
temperatures, that would be a nice reference.
Thanks.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html
lang...@fonz.dk
> OK -- slightly dumb question.
>
> What is a safe figure to assume for engine compartment ambient
> temperatures? Semiconductor companies seem to agree that the automotive
> temperature range is -40C to +85C, but that's at the part, and you need
> some temperature drop to the outside world for heat to flow.
>
> I'm sure the answer is some variation of "that depends on what part of
> the engine compartment", so to qualify, I'm thinking of places where one
> may reasonably mount electronics, like inner fenders or the firewall.
> If there were a chart somewhere that listed spots and expected high
> temperatures, that would be a nice reference.
>
> Thanks.
>
I checked a few datasheets for bosch motorsport parts, they rated an
ignition driver for -40 to +120C, an ECU for -25 to +85C, coil-on-plug
with build in driver -20 to +140C
Coolant will get to around 85C or so, as long as you stay away from
the
exhaust manifold I'd guess that could be a guide
-Lasse
Jim Thompson
wrote:
>OK -- slightly dumb question.
>
>What is a safe figure to assume for engine compartment ambient
>temperatures? Semiconductor companies seem to agree that the automotive
>temperature range is -40C to +85C, but that's at the part, and you need
>some temperature drop to the outside world for heat to flow.
When I was designing alternator regulators ad ignition systems, it was
-40°C to +140°C (chip temperature) that I had to design to.
>
>I'm sure the answer is some variation of "that depends on what part of
>the engine compartment", so to qualify, I'm thinking of places where one
>may reasonably mount electronics, like inner fenders or the firewall.
>If there were a chart somewhere that listed spots and expected high
>temperatures, that would be a nice reference.
>
>Thanks.
That's why you'll find much electronics located under the "kick"
panels in the passenger compartment ;-)
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Remember: Once you go over the hill, you pick up speed
whit3rd
> On 17 Feb., 20:00, Tim Wescott <t...@seemywebsite.com> wrote:
>
> > OK -- slightly dumb question.
>
> > What is a safe figure to assume for engine compartment ambient
> > temperatures?
> Coolant will get to around 85C or so, as long as you stay away from
> the
> exhaust manifold
No modern car has an 85C coolant temperature limit; these are
PRESSURIZED water systems. Plan on 120C if your location is on
the engine block, higher for exhaust system.
Fred Bartoli
> OK -- slightly dumb question.
>
> What is a safe figure to assume for engine compartment ambient
> temperatures? Semiconductor companies seem to agree that the automotive
> temperature range is -40C to +85C, but that's at the part, and you need
> some temperature drop to the outside world for heat to flow.
>
> I'm sure the answer is some variation of "that depends on what part of
> the engine compartment", so to qualify, I'm thinking of places where one
> may reasonably mount electronics, like inner fenders or the firewall. If
> there were a chart somewhere that listed spots and expected high
> temperatures, that would be a nice reference.
>
> Thanks.
>
Just received an add for some automotive components, qualified up to
150°C, and with a reference to some automotive standard, namely AEC-Q100.
That leads to http://www.aecouncil.com/index.html where you can freely
download a lot of stuff related to components qualification and
automotive quality standards.
No, I don't know what's inside...
--
Thanks,
Fred.
Joerg
> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
> wrote:
>
>> OK -- slightly dumb question.
>>
>> What is a safe figure to assume for engine compartment ambient
>> temperatures? Semiconductor companies seem to agree that the automotive
>> temperature range is -40C to +85C, but that's at the part, and you need
>> some temperature drop to the outside world for heat to flow.
>
> When I was designing alternator regulators ad ignition systems, it was
> -40°C to +140°C (chip temperature) that I had to design to.
>
Toasty, toasty. What's the MTBF you got out of that at 140C?
I received an email blurb from ST recently about a CPU from their STM8A
series that's supposedly qualified to 150C. But the link doesn't work
and their web site is quite screwed up. This is one of the companies
that should perform a summary firing of their whole web design team, IMHO.
[...]
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM.
Jim Thompson
wrote:
>Jim Thompson wrote:
>> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
>> wrote:
>>
>>> OK -- slightly dumb question.
>>>
>>> What is a safe figure to assume for engine compartment ambient
>>> temperatures? Semiconductor companies seem to agree that the automotive
>>> temperature range is -40C to +85C, but that's at the part, and you need
>>> some temperature drop to the outside world for heat to flow.
>>
>> When I was designing alternator regulators ad ignition systems, it was
>> -40°C to +140°C (chip temperature) that I had to design to.
>>
>
>Toasty, toasty. What's the MTBF you got out of that at 140C?
Silicon actually can handle it with ease.
One of my favorite customers was Schlumberger. They'd send one of my
hybrids down an oil well hole, where it'd be exposed to 200°C while it
took radiation data. Pull it back up, unplug it, discard it, and plug
in a new one.
I had them send me some discards for examination...
Specifications, still dead-on.
Only "damage" was discolored gold of the DIP package.
>
>I received an email blurb from ST recently about a CPU from their STM8A
>series that's supposedly qualified to 150C. But the link doesn't work
>and their web site is quite screwed up. This is one of the companies
>that should perform a summary firing of their whole web design team, IMHO.
>
>[...]
Joerg
> On Thu, 17 Feb 2011 18:09:33 -0800, Joerg <inv...@invalid.invalid>
> wrote:
>
>> Jim Thompson wrote:
>>> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
>>> wrote:
>>>
>>>> OK -- slightly dumb question.
>>>>
>>>> What is a safe figure to assume for engine compartment ambient
>>>> temperatures? Semiconductor companies seem to agree that the automotive
>>>> temperature range is -40C to +85C, but that's at the part, and you need
>>>> some temperature drop to the outside world for heat to flow.
>>> When I was designing alternator regulators ad ignition systems, it was
>>> -40°C to +140°C (chip temperature) that I had to design to.
>>>
>> Toasty, toasty. What's the MTBF you got out of that at 140C?
>
> Silicon actually can handle it with ease.
>
Ease? I've been warned by mfgs that the MTBF begins to drop seriously at
those temps.
> One of my favorite customers was Schlumberger. They'd send one of my
> hybrids down an oil well hole, where it'd be exposed to 200°C while it
> took radiation data. Pull it back up, unplug it, discard it, and plug
> in a new one.
>
You designed their gamma ray tool? We've used that on a rig out at sea.
But back then there were no ICs in it. The sono tool did but AFAIR
mostly processors. It's amazing how hot those sondes still are when they
pop back out on the derrick.
Schlumberger is a great company, I really liked them. They also had good
safety and environmental policies. Once I chucked a small remnant of
drinking water from my cup into the sea 50ft below. "Don't do that" ...
"But it's just water" ... "Yeah, but don't do that".
Jim Thompson
wrote:
>Jim Thompson wrote:
>> On Thu, 17 Feb 2011 18:09:33 -0800, Joerg <inv...@invalid.invalid>
>> wrote:
>>
>>> Jim Thompson wrote:
>>>> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
>>>> wrote:
>>>>
>>>>> OK -- slightly dumb question.
>>>>>
>>>>> What is a safe figure to assume for engine compartment ambient
>>>>> temperatures? Semiconductor companies seem to agree that the automotive
>>>>> temperature range is -40C to +85C, but that's at the part, and you need
>>>>> some temperature drop to the outside world for heat to flow.
>>>> When I was designing alternator regulators ad ignition systems, it was
>>>> -40°C to +140°C (chip temperature) that I had to design to.
>>>>
>>> Toasty, toasty. What's the MTBF you got out of that at 140C?
>>
>> Silicon actually can handle it with ease.
>>
>
>Ease? I've been warned by mfgs that the MTBF begins to drop seriously at
>those temps.
This was back in bipolar days.
>
>
>> One of my favorite customers was Schlumberger. They'd send one of my
>> hybrids down an oil well hole, where it'd be exposed to 200°C while it
>> took radiation data. Pull it back up, unplug it, discard it, and plug
>> in a new one.
>>
>
>You designed their gamma ray tool?
Yep. (Somewhere between 1970-1973) It was a hybrid, discrete
transistors and diodes (chips), thick film resistors, chip capacitors,
and, IIRC, TTL logic, on an alumina board, inside a dual-inline
gold-plated CAN ;-)
>We've used that on a rig out at sea.
>But back then there were no ICs in it. The sono tool did but AFAIR
>mostly processors. It's amazing how hot those sondes still are when they
>pop back out on the derrick.
>
>Schlumberger is a great company, I really liked them. They also had good
>safety and environmental policies. Once I chucked a small remnant of
>drinking water from my cup into the sea 50ft below. "Don't do that" ...
>"But it's just water" ... "Yeah, but don't do that".
>
>[...]
I always liked Schlumberger... nice bunch of guys.
Joerg
> On Fri, 18 Feb 2011 07:41:02 -0800, Joerg <inv...@invalid.invalid>
> wrote:
>
>> Jim Thompson wrote:
>>> On Thu, 17 Feb 2011 18:09:33 -0800, Joerg <inv...@invalid.invalid>
>>> wrote:
>>>
>>>> Jim Thompson wrote:
>>>>> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
>>>>> wrote:
>>>>>
>>>>>> OK -- slightly dumb question.
>>>>>>
>>>>>> What is a safe figure to assume for engine compartment ambient
>>>>>> temperatures? Semiconductor companies seem to agree that the automotive
>>>>>> temperature range is -40C to +85C, but that's at the part, and you need
>>>>>> some temperature drop to the outside world for heat to flow.
>>>>> When I was designing alternator regulators ad ignition systems, it was
>>>>> -40°C to +140°C (chip temperature) that I had to design to.
>>>>>
>>>> Toasty, toasty. What's the MTBF you got out of that at 140C?
>>> Silicon actually can handle it with ease.
>>>
>> Ease? I've been warned by mfgs that the MTBF begins to drop seriously at
>> those temps.
>
> This was back in bipolar days.
>
Ah, from the days of the Kennewick man :-)
>>
>>> One of my favorite customers was Schlumberger. They'd send one of my
>>> hybrids down an oil well hole, where it'd be exposed to 200°C while it
>>> took radiation data. Pull it back up, unplug it, discard it, and plug
>>> in a new one.
>>>
>> You designed their gamma ray tool?
>
> Yep. (Somewhere between 1970-1973) It was a hybrid, discrete
> transistors and diodes (chips), thick film resistors, chip capacitors,
> and, IIRC, TTL logic, on an alumina board, inside a dual-inline
> gold-plated CAN ;-)
>
Then I've seen your stuff decades ago, I repaired one in what we called
the "dog house". A short sea container off to the side of the caboose
where the winch and the computer was. No heater in there ...
Jim Thompson
wrote:
Scratching my butt while trying to remember... I thought it was alpha
particle detection ???
Joerg
> On Fri, 18 Feb 2011 08:37:59 -0800, Joerg <inv...@invalid.invalid>
> wrote:
>
>> Jim Thompson wrote:
>>> On Fri, 18 Feb 2011 07:41:02 -0800, Joerg <inv...@invalid.invalid>
>>> wrote:
>>>
>>>> Jim Thompson wrote:
[...]
>>>>> One of my favorite customers was Schlumberger. They'd send one of my
>>>>> hybrids down an oil well hole, where it'd be exposed to 200°C while it
>>>>> took radiation data. Pull it back up, unplug it, discard it, and plug
>>>>> in a new one.
>>>>>
>>>> You designed their gamma ray tool?
>>> Yep. (Somewhere between 1970-1973) It was a hybrid, discrete
>>> transistors and diodes (chips), thick film resistors, chip capacitors,
>>> and, IIRC, TTL logic, on an alumina board, inside a dual-inline
>>> gold-plated CAN ;-)
>>>
>> Then I've seen your stuff decades ago, I repaired one in what we called
>> the "dog house". A short sea container off to the side of the caboose
>> where the winch and the computer was. No heater in there ...
>>
>> [...]
>
> Scratching my butt while trying to remember... I thought it was alpha
> particle detection ???
>
Then we may be talking about a different tool. The one I repaired was a
gamma ray sonde.
Martin Riddle
"Joerg" <inv...@invalid.invalid> wrote in message
news:8s7mm9...@mid.individual.net...
Del used to make HV supplies for drilling, never seen the actual thing
up close, But it was for the drill bit tip. Made out of some brown
pressure formed material to take the heat.
Think Spellman still operates what is left of Del.
Cheers
Rich Grise
> Jim Thompson wrote:
>> On Thu, 17 Feb 2011 18:09:33 -0800, Joerg <inv...@invalid.invalid>
>>> Jim Thompson wrote:
>>>> On Thu, 17 Feb 2011 11:00:47 -0800, Tim Wescott <t...@seemywebsite.com>
>>>>
>>>>>
>>>>> What is a safe figure to assume for engine compartment ambient
>>>>> temperatures? Semiconductor companies seem to agree that the
>>>>> automotive temperature range is -40C to +85C, but that's at the part,
>>>>> and you need some temperature drop to the outside world for heat to
>>>>> flow.
>>>> When I was designing alternator regulators ad ignition systems, it was
>>>> -40°C to +140°C (chip temperature) that I had to design to.
>>>>
>>> Toasty, toasty. What's the MTBF you got out of that at 140C?
>>
>> Silicon actually can handle it with ease.
>
> Ease? I've been warned by mfgs that the MTBF begins to drop seriously at
> those temps.
>
>> One of my favorite customers was Schlumberger. They'd send one of my
>> hybrids down an oil well hole, where it'd be exposed to 200°C while it
>> took radiation data. Pull it back up, unplug it, discard it, and plug
>> in a new one.
>
> You designed their gamma ray tool? We've used that on a rig out at sea.
> But back then there were no ICs in it. The sono tool did but AFAIR
> mostly processors. It's amazing how hot those sondes still are when they
> pop back out on the derrick.
>
> Schlumberger is a great company, I really liked them. They also had good
> safety and environmental policies. Once I chucked a small remnant of
> drinking water from my cup into the sea 50ft below. "Don't do that" ...
> "But it's just water" ... "Yeah, but don't do that".
>
with their instructions and pre-measured wires and suchlike, they could
be assembled by a partly trained gorilla. ;-) (I know, because I watched
my older brother build the equivalent of a Harman-Kardan receiver.) ;-)
I once assembled an IO-10 'scope, but I screwed it up because I was
impatient and had too many beers - while I was in a tizzy over how to
fix a 'scope without a 'scope, one of my buddies offered to trade me
his Scelbi 8H 8008 computer even up - both were about $600.00 at the
time, and I'd been obsessed with computers ever since the Bendix/Control
Data G-15 computer in high school (class of '67):
http://members.iinet.net.au/%7Edgreen/docs.html
Cheers!
Rich
John - KD5YI
> OK -- slightly dumb question.
>
> What is a safe figure to assume for engine compartment ambient
> temperatures? Semiconductor companies seem to agree that the automotive
> temperature range is -40C to +85C, but that's at the part, and you need
> some temperature drop to the outside world for heat to flow.
>
> I'm sure the answer is some variation of "that depends on what part of
> the engine compartment", so to qualify, I'm thinking of places where one
> may reasonably mount electronics, like inner fenders or the firewall. If
> there were a chart somewhere that listed spots and expected high
> temperatures, that would be a nice reference.
>
> Thanks.
>
This is from SAE J1211 Revised NOV78:
TABLE 1—RECOMMENDED TEMPERATURE EXTREMES
Underhood
Location Maximum Temperature
-- Dash Panel 140 °C ( 285 °F)
-- Engine (Typical) 150 °C ( 300 °F)
-- Choke Housing 205 °C ( 400 °F)
-- Starter Cable Near Manifold 205 °C ( 400 °F)
-- Exhaust Manifold 650 °C (1200 °F)
John - KD5YI
>
> What is a safe figure to assume for engine compartment ambient
> temperatures? Semiconductor companies seem to agree that the automotive
> temperature range is -40C to +85C, but that's at the part, and you need
> some temperature drop to the outside world for heat to flow.
FYI, Cypress' Automotive qualified parts are specified to 105C.