The initial results for the 2020 motor performance DOE’s are in. The data that will be shown here is the average of the entire set. For now, the highs & lows and the impact on the other three variables are not discussed.
First, the capacity to pull cars on a 2.5% grade is shown in the following figure.
The average number of cars pulled for all tests is 22.3 cars. The minimum average is 20 cars for the Rapido motor. The exceeds the nominal train number of 8 or 12 cars by a considerable number. he nominal number is determined by the factor of 2 times the number of drive axles. This for these tests, all the motors do a excellent job, some do much better than others.
This difference is highlighted in the following figure. Here the difference between what the motor will pull compared to the average is defined as a percent of the average. As shown, the difference from the worst to the best is more than 25 percent of the average. The Mashima 1833 #1 motor is the clear winner in this parameter. The Rapido is the poorest puller. The Atlas Genset and the Athearn Genesis motors also fall significantly below the average.
The next aspect is nominal strain speed. Clearly this is driven by the voltage speed function of the motor. Initially the Sagami 1836 #1 motor was screened out because its rpm voltage function was low. Because other motors also have slower then desired RPM curves, it was brought back in for an overall examnation. The next chat shows the speed result on a level surface.
The Canon C-22, Athearn Genesis and the Atlas China #2 motors yield the fastest train speeds. The Sagami 1836 #1, Atlas Genset & the Walthers ES44 are the slowest.
An interesting impact is the speed impact of the train as the grade goes to 2.5%. There is a substantial loss in the train speed. All motors lose speed. The Atlas China #2, Canon C-22 and the Chinese motors are now the fastest. The Sagami 1836 #1 and the Atlas Genset are the slowest.
Looking at the percent speed loss shows an interesting result. The motors with the least speed loss are the Chinese motor, Atlas China #2 and the Mashima 1822 #1. The motors with the greatest speed loss are the Sagami 1836 #1, Rapido and Atlas Genset.
The lowest performing motors in several of these parameters are the recently released candidates. These have been selected because of their impact on current draw and noise. The power(current draw) will be discussed in another post. Noise was not part of this activity because the test bed engines were not designed for reduced noise. It is a more complex problem then this series was equipped to handle.
A very quick assessment, based on additional data not shown in this post, shows the motor rank as follows:
- Atlas China #2
- NWSL 163-4 Sagami
- Chinese motor
- P1K #2
- Canon C-22
- Athearn Genesis
- Mashima 1833 #1
- Athearn High Performance #2
- Mashima 1824 #1
- Atlas Genset
- Kato #2
- Bachmann Plus #2
- Walthers ES44
- Rapido
- Sagami 1836 #1
The top four are clear winners. The bottom three all are short on many fronts.
In general all of these motors are adequate for the application. One may put more emphasis on certain aspects than others. That would change the ranking.
I am working on assessing the full aspects of the results and will be publishing a more specific conclusion post when that is completed. Watch for it. See here for more details:
Design of Experiments design-
https://www.llxlocomotives.com/?p=2433
Initial activity-
https://www.llxlocomotives.com/?p=2360
Detailed results-
