Can you MU power with different gear ratios? My guess is you can or there would be a mess in scheduling loco combinations. If “yes” is the answer, explain how it is so. Seems that wheels would turn different rpm’s.
Northtowne
Yes you can. In the days before modern computer control systems it was best if the highest speed geared locomotive was the controlling locomotive to avoid running it at full power, at a speed below its minimum continuous speed for time periods enough to melt the insulation in the traction motors. With the Engineer in the cab of the highest geared locomotive he could monitor the load meter.
See Al Krug’s explanations of such matters on his “Amperage to Tractive Effort Table” or “Amps vs Tractive Effort” webpage, answer 1., at: http://www.alkrug.vcn.com/rrfacts/amps_te.htm
The other related topics in his “Railroad Facts and Figures” compilation, such as “Drawbar Limits” and “Horsepower vs Tractive Effort” on http://www.alkrug.vcn.com/rrfacts/rrfacts.htm , are also informative.
I’m sure this question or a similar one has been discussed here before. It might also be worthwhile to either search or post your question over on the “Locomotives” Forum here as well, at: http://cs.trains.com/TRCCS/forums/741.aspx For instance, see:
“Multiple locomotive operation” from Jan. 2010 at: http://cs.trains.com/TRCCS/forums/p/167151/1838447.aspx#1838447
“How do they syncronize locomotives” (sic) from Jan. 2008 at: http://cs.trains.com/TRCCS/forums/p/114639/1315471.aspx#1315471
“operating multiple engines” from June - July 2008 at: http://cs.trains.com/TRCCS/forums/p/131270/1475530.aspx#1475530
- Paul North.
So the traction motors on the lower geared locos would receive more current (amps?) making the axles (wheels) turn faster to match the speed of the higher geared locos. Is this basically what happens? I have to have it simple as I do not grasp even the basics of electricity. Thanks all for your help.
Northtowne
The “WHEELS” all turn at the same speed… At least the tread-surface feet-per-minute must be the same on all the locomotives, lest one locomotive is not providing tractive effort at all! It is the traction motors that would be turning at different speeds to keep the wheels all running at the same speed.