SNAG: Re: Got 4Ah, not 5Ah, battery 18V (20V) - done right thing?

On 5/19/2024 4:17 PM, Jim Wilkins wrote:

"Bob La Londe"  wrote in message news:v2djrv$3hfus$1@dont-email.me...
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On 5/18/2024 7:33 PM, Jim Wilkins wrote:
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I never was employed doing destructive testing, but I did spend a decade
or two doing low voltage communication contracting.  I learned there is
what they say, and there is what there is.  Usually what they say fell
short in my field, but sometimes it didn't.
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When they say an IR motion sensor will detect motion at 90 feet they
mean if ambient is below 70F and the subject is large and is running a
fever.  LOL.  They don't say if ambient is 90+ its virtually worthless.
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Most of the testing was to find and reject or reclassify parts that didn't meet specifications for companies that cared, or burn-in testing to weed out early failures by operating at elevated temperature for a week. The exact conditions were usually secret, I had to provide a range of adjustment. Sometimes there had to be provision for destructive failure, such as Chrysler Lean Burn engine controllers with components not rated for possible under-hood temperatures.
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Before Congress mandated emissions and fuel economy standards that needed electronic control to meet, the only electronic device in a car was the radio which the auto makers bought, they had to hire new engineers unfamiliar with the heat, water, dirt, salt and vibration, who took time to learn. I had the partial advantages of military electronic experience which solves those, in commercially unaffordable ways, plus a hands-on apprenticeship in custom electro-mechanical machine design. The engine compartment environment can be nearly as challenging as military aircraft specs, consider a snow plow driver in Alaska starting cold and diving full throttle into the deep snow in front of the truck, or splashing through an icy puddle.
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Heat in the South is another issue that's not so evident in Michigan. I know what Atlanta is like in summer.
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  Bell Labs had material test sites down here in the Sonoran Desert for environmental testing.  Death Valley may be the only place in North America more hostile than the low Sonoran Desert.  They had panels setup with material samples affixed out along the southern rail line right of way.  Maybe they still do (if they are still some form of Bell Labs).  I haven't checked in a long time.