The World’s Fastest & Most Accurate Smokemeter - The CalTest 1000 (Results of Smokemeter Correlation Testing, under the auspices of the SAE J1667 Committee, of six brands of smokemeters, at Golden West College Diesel Laboratory)
During the four days of testing of paired smokemeters on twinstack test stands, the CalTest 1000 operator often had to wait for several minutes, f or other meters to catch up. The Bosch RTT-100 had to get its internal pressure and temperature up to manufacturers specifications and zero, etc. That took an unimpressive 7 minutes. The CalTest 1000 took less than 1 minute for zeroing, etc.. All brands except the CalTest 1000 had to start all over...recycle (Bosch time: 2.5 minutes) if there was a glitch in testing, such as the need to re-do soot-purging snaps or test snaps. In sharp contrast, by pushing a keyboard key recommended on its LCD display, the CalTest 1000 was made instantly ready for either action.
The World’s Most Accurate Smokemeter. The CalTest 1000 was the most accurate in both test categories:
In “within manufacturer” tests, the two CalTest 1000 meters (Unit 1 vs. Unit 2) had the greatest performance consistency, with Predicted Differences at 95% confidence, 95% population, within:
- CalTest 1000 + 2.1% (Best) Full flow smokemeter
- Wager 6500 + 2.8% Full flow smokemeter
- Berkeley 300 + 3.0% Full flow smokemeter
- GEC (Wager 6700) + 3.3% Sampling smokemeter
- Bosch RTT-100 + 3.8% Sampling smokemeter
In “among manufacturers” tests (Brand A vs. Brand B) the CalTest 1000 had the two closest correlation’s with other brands, with Predicted Differences at 95% confidence, 95% population, within:
CalTest 1000 (CalTest vs. Berkeley: + 3.2%. CalTest vs. Wager: + 3.5%) + 3.5% (Best)
The Closest correlations of other brands with any two of the three (CalTest, Berkeley & Wager) were:
- GEC (Wager 6700) (GEC vs. CalTest: + 6.1%. GEC vs. Berkeley: + 5.5%) + 6.1%
- Berkeley 300 (Berk. vs. CalTest: + 3.2%. Berk. vs. Wager: + 6.3%) + 6.3%
- Wager 6500 (Wager vs. CalTest: + 3.5%. Wager vs. Berk.: + 6.3%) + 6.3%
- Bosch RTT-100 (Bosch vs. CalTest: + 8.0%. Bosch vs. Wager: + 8.0%) (Worst)
DEFINITELY, THE CALTEST 1000 IS THE WORLD’S MOST ACCURATE SMOKEMETER.
 Engineers recommend against long-hose sampling meters (Bosch RTT-100 & a sixth meter):
The sixth meter did so poorly its name and data are omitted above by manufacturer’s request
Four technical engineering papers give warnings (which 1996 tests proved to be valid) about using Bosch-type meters for transients (In snap-acceleration testing, opacity can jump 60% or more in 1/10 second.):
SAE J1157: “Sampling type light extinction meters have inherent design limitations for accurate measurement of transient smoke concentrations.”
SAE J35: “Slow responding or sampling, or both, type instruments must not be used since they typically have excessive or variable response delays and do not provide an accurate measurement of an engine’s transient smoke characteristics.”
SAE J255a: “OPACITYMETER, SAMPLING TYPE...Transient smoke measurements with this type of instrument are not recommended due to slow system response, problems of obtainging a representative exhaust sample, and inability to maintain temperatures and pressures within specified limits during transient operation of an engine.”
ISO/DIS 11614 (1995): “Many [sampling] opacitymeters of established designed cannot achieve a [total response time] of less than 0.4 sec...[making them unsuitable for testing rapid transients].”
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California Air Resources Board passed new emission laws for on- road heavy duty diesel trucks. If you're a California fleet operating company you are required to make necessary changes to your fleets to have clean emissions in order to stay in business over the next decade.
opacity tests not only test emissions in the way that makes sense under the SAE J1667 rules and keeps you in compliance with the EPA so you can avoid their fines, we can also due snap idle and under load testing to cover all the emission bases for your records.
Approved by NI Dept. of Environmental Protection for SAE J1667 snap-acceleration, stall and rolling-acceleration tests. Four snap-acceleration tests available not just the SAE J1667 snap test. California State Certified Emissions Staff!