|
|
| Re: Brake Valve portion Re: LIRR MP-54 #1149 and its ME-23 brake valve (485817) | |||
 |
|||
| Home > SubChat | |||
|
[ Read Responses | Post a New Response | Return to the Index ] |
|
||
|
Re: Brake Valve portion Re: LIRR MP-54 #1149 and its ME-23 brake valve |
|
|
Posted by Jeff H. on Tue Sep 4 19:41:51 2007, in response to Re: Brake Valve portion Re: LIRR MP-54 #1149 and its ME-23 brake valve, posted by Bill West on Mon Sep 3 05:21:58 2007. A similar magnum opus is something I have been working on toexplain the design and maintenance aspects of traction air brake equipment. Much has been written about mainline RR stuff, but comparitively little about traction. Regarding emergency dynamic braking: Yes, it is required that the motors be placed in parallel and the fields reversed compared to the motoring direction. This creates a figure-8 loop in which the EMF generated by each motor has a complete circuit via the other motor, which leads to build-up of dynamic brake current and torque. If the motors were left in series, well, first off the circuit would be entirely open unless a ground were applied instead of the Trolley connection at the line switch, and secondly the relative polarity of the voltages and currents would not be correct to create braking. |
|
|
|